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PANomad

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Posts posted by PANomad

  1. Hi Moses,

     

    I changed out the oil pressure sensor, and cleaned up the center connection in the PCM.  It's only been a few days but it seems that the oil is not building up in the connector anymore. If the oil starts to build up again in the connector over the next week or two I'll let you know, but for now it seems like that was the problem.   The "noise" is still there, but I'm attributing this to a symptom of old age.

  2. Last night I got home later than I would have liked but still had some time to work on these issues.  I was able to replace the cracked fitting on the end of one of the vaccum lines going from the LDP to the intake, and while I was at it, I replaced a few more that looked like they might crack in short order.

     

    I also replaced the drives side door handle.  This is what took most of my time.  The door handle I received from Quadratec did not have threaded holes for fastening to the door, and I couldn't find M5-16 screws or a tap at either the auto part store or the nearby Lowes.  The closest Jeep dealer was too far and closed for the day so I opted to buy an M6 tap and the corresponding screws instead.  This worked out just fine, except I had to put a few extra washers under the head of the bolts to take up the extra length on the bolts.  I couldn't get screws any shorter at Lowes.  You can't see them because they're inside the door, they don't interfere with the mechanism, and they hold the handle in place securely so I don't plan to source shorter screws from another supplier.  I don't expect an issue with the door handle coming loose, but I did save the factory handle just in case.  Overall including the drilling and tapping it took about an hour to install.

     

    This morning when I left for work the door wouldn't release.  I checked it last night after installation and it worked fine...  I ended up taking the interior door trim back off and found the clip that holds the connector rod to the latch had slipped off or it was never attached properly last night (it was dark, I could barely see, and I was going by feel inside the door at that point).  A little aggravating but a quick, easy, 10 minute fix.

     

    Since it was dark I didn't have time to check the CPS or oil pressure sensor for leaks, but...  After I left the house this morning my check gauges light came on, and a warning tone sounded, then both went away.  As first I didn't notice what for but a few miles later I noticed my oil pressure gauge dropped to zero at a stop sign.  So...  I think that more than likely answers the question on faulty sensors...  I will have a look tonight and see if the CPS is leaking or anything out of the ordinary, but I will be picking up an oil sensor and installing it tonight.  I'll keep an eye out for signs of oil that would be wicking up the wires to the PCM.

     

    I'll also be cleaning the PCM out again, hopefully for the last time, and hopefully the odd knocking goes away with a clean oil free PCM.  I'll keep you posted how I make out.

  3. Moses, I thought the same thing when I first read about the capillary action and wicking oil up inside the insulation on the wires all the way from the oil sensor or the CPS.  I need to take another look with this in mind tonight, but when I cleaned the connector two weeks ago I noticed a damaged section of insulation and there was oil on the wires.  I had already sprayed the contact cleaner on the plug at that point and I assumed it had run down out of the plug.

     

    That being said, I sprayed more contact cleaner on the plug as many times as I needed until it stopped seeping oil, then let it dry.  When I pulled the plug out yesterday I half expected to see a little bit of residual oil that was stubborn and didn't want to come out from my cleaning, but  didn't expect to see the entire plug covered in almost as much oil as before I cleaned it.

     

    I still don't know if I believe this is the cause, because there was no evidence of oil anywhere else around that area of the engine compartment, and I would think that air movement from driving would have made an adjacent area at least a little damp...

     

    I'll let you know what I find.

  4. Moses,

     

    Looking at the schematic you attached, the screws are actually item 5.  They are to attach the door handle itself (item 7) to the door.  They don't seem to be self tapping from the schemaitc, but the thread is listed M5x16.  I called to double check with the dealer, and they confirmed the thread size.  Actually, I called them this morning and the guy said he didn't have a thread size only a part number.  When I called them after your post to see if he could confirm 100% the self tapping characteristic I got a different guy, and he confirmed the size without me giving it to him first.

     

    Even though I'm confident I need the tap, I'll pick up some self tapping M5 screws along with a tap while I'm at the parts store today just in case.  I can always return the tap if I end up not needing it for the install.  I haven't needed an M5 tap in the past 10 years so I doubt I'll need it anytime soon outside this project...  If it turns out I didn't need the screws, I'll put them in an empty harware bin on my shelf.  I'll use them eventually.

     

    Thanks for the help!

  5. The paddle handles on the ouside of my TJ drivers door is difficult to open and usually remains stuck open.  The paddle is twisted inside the rest of the housing so I'm assuming there's a bushing that has worn out and now causing the paddle to rub against the housing.

     

    I ordered replacement handles from Quadratec, and when they arrived I found the two bolt holes that hold the handle assembly inside the door are not tapped.

     

    Does anyone know what size thread this hardware is, so I can get the correct tap and complete the installation???  I plan on calling the parts desk at the Jeep dealer, and hopefully they can locate the bolts and provide this information to save some time.

  6. Hi Moses,

     

    After posting the photos last night I was searching the web for anything about an oily residue in PCM contacts.  I found several posts for several different vehicle manufacturers related to engine oil leaking from a sensor and wicking up the wiring harness into the PCM.  The descriptions and photos I found are exactly what I am seeing.

     

    When I originally posted about it two weeks ago, I can tell you that the oil was there before I cleaned the connections with electrical contact cleaner (allowing proper drying time afterword) and used the dielectric grease.  I don't think the residue is from the grease since it was there before I put it on.

     

    I found information related to the 4.0 in a Cherokee with engine oil seeping into the PCM.  One of the forum users who responded was a mechanic and had seen this issue before.  He said to check the crank sensor or the oil pressure sensor for an oil leak.  The original poster did not confirm this was the case and solved the problem, so I don't know for sure it was correct.  On a Dodge Neon forum there was a very similar post and it was suggested to check the crank sensor, oil pressure sensor, and cam position sensor for leaking oil.

     

    When trying to diagnose the Cylinder 6 misfire I was having my crank sensor was ruled out because if it was not working the Jeep just wouldn't run.  Do you agree with this assessment, and if you do is it still possible there is a leak around the sensor even though it is working?  What about the cam position sensor?  If it was damaged and leaking oil would it function correctly?  I am not getting and DTC's other than the P1486 (pinched evap hose), and I would expect to get a code for either the crank sensor or the cam sensor, however I can see possibly causing the knocking/pinging issue that just started.  Coincidence?

     

    I replaced the oil pressure sensor about 3 years ago, but that doesn't mean it isn't leaking.  I'm just wondering if it's more likely one of the other two sensors due to the engine issue...

     

    Regardless, I am planning to pick up those vaccum hose connectors to replace them tonight, and I also have to replace the drivers door handle assembly (which sticks open sometimes).  Hopefully I can get underneath and assess these sensors before I lose daylight after work.

  7. OK.  So I finally had the time to make these quick checks.  I took the vaccum readings at the MAP at idle and the needle holds steady at 17.  It drops initially as I apply throttle, and then smoothly climbs to about 22 at nearly full throttle in neutral.  I tested the MAP sensor itself and it's working correctly.

     

    While I was testing the MAP sensor I found the end of one of the vacuum lines going to the LDP is split and probably causing the P1486 code.  I checked all of the other vacuum lines and connectors again and didn't find anything else wrong.   I'm going to go to the parts store tomorrow and get a new connector and hopefully that takes care of the P1486 code.

     

    I replaced the gas cap a week ago and the P0455 code has gone away since then.  I didn't suspect it was the cap at first because it was a brand new cap.  The parts store must have given me the wrong part.

     

    I also changed out the half torn-ground wires and replaced with new ones.

     

    I pulled the center PCM plug out again to see if it looked better than it did before I cleaned it two weeks ago, and it looks almost as bad.  I would post the two pics I took, but I'm not sure how to do that on this forum...  The pins and plug are filled with some kind of oily black liquid.  Do you think this could be causing the knocking or pinging that I mentioned just started about two weeks ago?

  8. Moses, I checked the pcm connections tonight. There are three plugs that plug into it and the two outside plugs and the corresponding pins were clean. The middle plug was filled with what looked like engine oil and the electrical tape wrapped around the wire bundle going into the plug was worn through in one spot.  The insulation on the wires inside was intact.  I cleaned all the plugs and the pins with electrical cleaner, and applied dielectic grease before plugging them back in.  I found the ground strap from the block to the firewall was dangling, but the other grounds were ok.  I pulled the ground screew out and for a temporary fix fished the loose ground ribbon through the hole in the other ground so the screw would capture it and make a connection.  I'll replace the ribbon altogether after I get to the parts store.

     

     I ran out of light before I had a chance to check the vacuum, but I went out for a quick drive.  The knocking/pinging was still there at the same RPM, but the engine was running and idling much more smoothly.

     

    Thanks for the engine code info.  I did not see that much info for each of the codes before now.  I guess I'll get a new gas cap while I'm picking up the ground ribbon, and I'll let you know the vacuum after I check it.

  9. Hi Moses,

     

    I got home too late last night to be able to check anything we discussed, but this morning on my way to work I noticed a noise that I haven't heard before now.  It sounds like something is rubbing/vibrating at high speed and it seems to start when engine revs get to about 1500 rpm.  Around 1700 rpm it goes away and the slower rattle can sound starts.  If I get off the throttle while it's happening, it goes away.  I'm not sure it is happens above 1700 rpm because there is too much noise from the exhaust, road, and loose interior door panels to hear it at that point.  I'm not sure if this is called pinging (because I don't think I've experienced it before) or if it's something else.  I know pinging is bad, so how can I tell for sure if that's what's happening?

     

    I plan to check the electrical connections and ground, and reset the PCM tonight.  If it goes away for my drive to work tomorrow I'll let you know.  I'll check the vacuum pressure tonight if I can as well.  I'm not sure I know how to check the function of the MAP sensor, but I plan to look it up.  Unless you have a quick procedure you can give me...

     

    BTW...  No change in the DTC's.  Still P0455 and P1486. And to answer one of your earlier questions, I don't have any performance chips, programmers, or other software upgrades.

  10. Moses, I see you suspect a PCM issue now that I've posted the history on my Jeep for the last several months.  I will check the connections to the PCM because I have never checked these yet, and I don't think the mechanic I had been taking it to did either.  I also want to check the vacuum at the MAP.

     

    I also plan to check the grounds.  I know there is a big one at the firewall, but can you let me know where the other(s) are?

  11. Hi Moses,

     

    In my first post, I meant to say great job on the magazine and forums.  I've been on other forums and none are as well organized or provide as much valuable information as your does.

     

    I joined this forum because a few months ago I found and followed through the post on #1 misfire.  At the time I was having a #6 misfire and no luck troubleshooting or addressing it.  Last year my wife and I had out first child, and we live in the country about 45 minutes from where we work.  I had just enough time between working for a living, taking care of my responsibilities at home, but with the adjustments to life as a parent I decided to let the local mechanic do the troubleshooting and repair work on our vehicles.   By the time I had found the post on your forum I had replaced several parts.  The history goes a bit like this:

     

    The P1486 DTC came and went intermittently for about 8 months.  Initially the local garage replaced some hoses and each time the code disappeared for several weeks, but then last fall it came on and they couldn't find anything wrong.  They checked all the hoses and components but couldn't find anything wrong.  They did a smoke test and couldn't find any leaks, so they recommended I take it to the dealer rather than going through the "parts repacement trials" you mention.  The Jeep ran OK and I didn't want to deal with the dealer (the local dealers don't have a very good reputation for honesty) so I put it off and tried to use the forums more heavily and find a solution.  I couldn't find anything.

     

    Before I did anything else, about 2 months later I noticed the Jeep was running rough and performance was down (low power).  I checked for additional DTC's using the method with the key in the ignition and found a P0301 code along with the P1486 code.  I took it to the garage rather than looking into it myself and they did a power cleaning of the fuel system (not just a bottle of fuel injector cleaner in the gas tank), and replaced two of the O2 sensors that were out of spec.

     

    The Jeep was happy for a while after that, but then it came back with a P0306 code and another code for one of the two catalytic converters ( I forget if it was bank 1 or 2) in the down pipe between the exhaust manifold and the larger cat in front of the muffler being bad.  The pipe with the two cats was replaced.  Again it was happy for about a week or two, then came back with the P1486 and P0306 codes.

     

    At this point there was 2 feet of snow on the ground and temps were in the single digits for the week.  I don't have access to a garage or a warm dry place to work, so I took it to another shop hoping to get out of the parts replacement trials.  They replaced the bar with the three coil packs in it for the ignition.  After this it was happy again for about a week or two, and then you guessed it.  I got a P1486 code followed by a P0306 code again.

     

    It was still freezing so I asked around for recommendations on a better mechanic, and was pointed to one near work.    By this time I has seen the #1 mnisfire thread on this forum, and suggested the perform a cylinder leak down test because I wasn't sure how to do it and it was freezing cold.  They checked compression, inspected the injectors, checked fuel pressure, etc. They diagnosed it to be a clogged fuel filter because it had never been replaced (it's in the gas tank) and the Jeep would not show a misfire while they had it running either in the shop or on the road. I opted to have the filter replaced because I suspected that myself, but at the same time had them replace the entire fuel pump assembly because of the age and the fact that my fuel gauge would drop to empty sometimes when my tank got to around 1/3 of a tank and not come back until I filled the tank.  The new fuel pump assembly made a noticable difference in the performance of the Jeep until the P0306 code came back on a week later along with the P1486 code.  They checked it again and it would not misfire at all while they had it running in the shop or on the road.

     

    About a week later my Jeep would not start after I got gas on the way to work.  I had it towed to the garage hoping whatever was causding the ghost misfire had finall failed and it would be obvious what was wrong.  It turned out to be a bad battery.  Having seen the voltage issues in the #1 misfire hread I was hopeful this was the problem.  A week later the P1486 and P0306 codes were both back and on top of it my steering box started leaking badly.

     

    I took it to the garage again to have the steering box replaced.  They cleared the codes after checking again for the cause of the misfire, and finding nothing.  About a week later (this is getting old hugh) the 1486 code was back and I was driving home on the interstate when my cruise control stopped working.  I turned it back on and a few seconds later it shut off again and would not turn back on.  Before I got home I noticed the Jeep was lacking power on a steep hill so I checked for the P0306 code when I got home.  There was no misfire code, but I had a high voltage code on the TPS.  I also noticed my horn wasn't working.  Looking up these symptoms on the forums led me to believe my clockspring was bad, so I ordered a new clockspring from the dealer.  By the time the new clockspring came in my cruise started working again.  I replaced the clockspring anyway figuring the garage likely damaged it when they had the steering gear disconnected.  I didn't think it was a coincidence otherwise I wouldn't have bothered with the $300 clockspring.  The TPS code didn't go away so I replaced it.  I didn't have time to go to the dealer and the sensor I got was a duralast from Autozone, but so far I have not gotten a new code for the TPS.

     

    The battery was disconnected when replacing the clockspring so the MIL was out for about a week again before it came back on with the P1486 code and about a week later I noticed low power and found the P0306 code.  I called the garage to let them know what had gone on since they had it and see if it shed any light.  The tech that had worked on my Jeep each time said he had been looking on forums after the last time I was there and was convinced I had an exhaust valve or two that was sticking enough to give me an intermittent misfire and throw the DTC.  I ran seafoam through the engine, then a bottle of Chevron Techron in the gas tank.  The P1486 code came back in the usual weeks worth of time, and this is when I replaced the charcoal canister and purge solenoid.  When the 0306 code came back three weeks later I ran another can of seafoam through the engine, added the proper amount to the engine oil, and half a bottle in the gas tank, then changed the oil a few days later.

     

    That was about a month ago, and the 0306 code has not yet returned, but the 1486 code has always come back within a week of the MIL being turned out, and now last week I also have the 0455 code.

     

    I don't know whether the misfire "ghost" and the 1486 code are related.  Reading the #1 misfire post as well as other posts on this forum, there were times when things seemed to match up but I'm lost.  I have a mechanical engineering background working mainly with very large grinding mills in the mining industry.  What I know about cars I have learned from working on my Jeep and the cars my wife has had over the past 12 years, and I was lucky that most issues were minor and I was able to easily diagnose the issues.  I am not confident at all when it comes to the electrical system or the sensors involved with the OBD2 system because until now I have not had to deal with them.  I am willing to learn, and when joining this forum hoped to be pointed in the right direction.  It isn't 9 deg F outside right now, so I don't plan to rely on the local garage either.

     

    Sorry for the very long post, but I wasn't sure which information was useful and which wasn't even though I realise some more specific information may have been more useful but I don't have it because I left the diagnostics to the local garage until now.

     

    Since the TPS was recently replaced and from what I have seen the Duralast is often acceptable, I'm going to rule out a malfunctioning TPS for now.  I'll check the threads to see how to check the MAP sensor as soon as I have time (probably during the weekend) and will let you know what I find.  I'll also check for a diagram that shows how the vaccum hoses should be routed for the evap system since two different shops worked on it before I touched it and I can't be certain they didn't cross a hose.

     

    If anything else jumps out for me to check based on the additional info I provided in this novel let me know, and thanks for the help so far!

  12. I have an update on my previous post.  I noticed some valve knocking yesterday climbing some steep hills on my drive home so I checked to see if any new codes popped up since I last checked a few days ago (the MIL has been on this whole time).  I still have the P1486 code, but I am now getting the P0455 (evaporative emissions gross leak) code as well.  Is this logical?  Can I have both a leak and a blockage and the OBD will catch them both at the same time?  I checked my gas cap which was tight, and hissed when I opened it...  I checked all the hoses around the charcoal canister and LDP again and still don't find any tears, cracks, etc...

  13. I need some help troubleshooting the possible causes for OBD code P1486 on my 2002 TJ.  The MIL has been on for weeks now with this code because I cannot figure out the problem, and three repair shops have not been able to figure it out either.

     

    P1486 is a kinked hose in the evaporative emissions system.  I have checked the hoses between the charcoal canister and throttle body, etc, and do not find any kinked hoses or hoses with a blockage.  The first repair shop thought this was caused by a leak, and did a smoke test but found no leaks.  The third shop thought there was a problem with my gas cap, but it was replaced with no change.  All of the shops could not find anything conclusive and suggested I go to the Jeep dealer for diagnosis.

     

    I have read up on the components of the system and the automatic tests it performs, and if I understand correctly the leak test is the first test run on this system followed by a blockage test.  I assume the leak test passed because I do not have a code for a leak, only the kinked hose.  Using this assumption I ruled out the leak detection pump needing replacement.  Since the hoses were all OK, I decided to forego the trip to the dealer because the charcoal canister and purge solenoid cost less than what the dealer would charge to diagnose for an hour.  I replaced the canister and solenoid.  When replacing the canister I found one of the hoses was cracked where it attached to the canister so I cut off enough length to get rid of the crack.  No other cracks or blockages were found in any of the hoses.  The MIL was reset by disconnecting the battery.  Three or four days later the MIL was back on with the P1486 code again.

     

    I don't know where else to look and would rather not go to the dealer and risk them not finding anything but still paying their diagnostics and labor rates. Any suggestions?

     

    The Jeep runs well most of the time, but since the MIL is lit all the time I don't know if there is another problem coming up.  This is even more annoying because I am getting an intermittent misfire code about once every two to four weeks which sends the computer into limp home mode and causes performance issues.  I can't tell right away that this has happened because the MIL was already on for the emissions fault, which means I can't be sure what driving conditions I was in when the misfire occurred.  The same shops were looking into the misfire and the engine would not misfire at all while they had it.  I'd really like to take care of the emissions issue so I might have another clue to add for solving the misfire.

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