wondernad

So I was able to install a new CTS and oxygen sensor. Took a drive while watching scan data. Data still showing it as running rich. Made a small pitstop to ship a package and when I tried to restart it wouldn't until I held the accelerator to the floor. I also experienced a single backfire on slight decel. I borrowed a compression gauge but couldn't get a leak down tester yet. Compression was 140, 148, 149 & 150. Checked fuel flow while cranking engine, fuel came out of supply in steady stream seamed like it was good flow. Had it stalling at the end of my test drive but i believe it is fuel level. Gauge is inop so I fill by mileage. I think one of my kids may have reset my trip meter. Still thinking about either a bad CPS or ECU due to rpm reading. With the scan tool at 50 mph in 4th gear it was reading around 1500 tach was around 2300. In my experience it feels like the tach is more accurate. I have another ECU somewhere. Just have to find it to see if anything changes.

Thanks for the response, so I have set the base timing by getting to TDC and dropping the distributor in as it rotates to the 6 o'clock location. I have also checked timing with a light. Cannot find any spec for it though. Idle timing sits around 10-12 degrees BTDC. which I feel is reasonable. When throttle input is applied the timing does advance. I will check fuel volume and manifold vacuum when I get a chance. Though another symptom popped up yesterday as I was looking at it. When I started it it ran fine for a few seconds then sputtered and choked out with smoke coming out of the intake hat. Would not restart right away. I connected the modis and found that the coolant temp was reading 39 degrees. Which it must have been closer to the low 100's. So I did the wiggle test of the CTS. The input would vary a lot. I was able to get it to read properly for a moment and it ran fine when started. Idled for a while and choked out again CTS reading low again. Obviously the ecu is dumping fuel in because it thinks it needs it for cold situations. I have ordered a CTS should be here Tuesday. I have a new air filter and have verified that the flexible pipe from air filter housing to t-body is clear. I verified the vacuum hoses when I replaced the cylinder head. I'm assuming also the valves aren't leaking since I had new valves installed and head checked by a reliable machine shop. I printed out the vacuum diagram and had it on hand when putting the intake and throttle body back on. Vacuum reading is right around 15 at idle.. The needle vibrates but doesn't sway As I have replaced the timing set I don't think it's out but I wasn't very confident in my marks. How would I go about checking the valve timing without tear down of the cover? One last thing I saw yesterday with the scanner. The fuel trims seem to be rich even when the CTS is reading. Scale of 0-256 where 128 is stochiometric reading 30s to 50s which is rich. So I am wondering if my O2 is going out as well. Haven't gotten to compression and leak down yet. Though I had done them previously and the only cylinder I had a problem with was the one with the crack in the head. If I remember correctly the leak down for 1-3 was around 15% and compression around 145 with a gauge I believe reads low. Cyl 4 had 85% leak down I think and 70 psi compression. I have not confirmed compression or leak down yet. I'll have to get the tools to do it.

The tires are 31's. The engine is bored 20 over. Everything else is stock to my knowledge. I haven't changed gears and am assuming the previous owners haven't either. I have checked tps adjustment, fuel pressure(14 psi), WOT adjustment and ISA motor is adjusted. All of the sensors react to throttle input when looking at the scan data.

Hi, I've been hunting and chasing my tail to get some kind of throttle response from my wrangler above 45 MPH. I know these are not very powerful to start but I feel like what I'm experiencing is abnormal. Anywhere above about 45MPH when throttle is given There is little or no response from the engine. I have gone through the tuning and troubleshooting, replaced numerous things and adjusted what is able to be adjusted to the best of my understanding. Most recently I put a new cylinder head on due to a cracked web between valves on cylinder 4. I was so sure this was going to solve my issue considering the cylinder was down to 70psi compression. Though the engine runs smoother and quieter now it still is lagging at higher speed. 5th gear is pretty much useless unless going down hill. I have access to a modis scan tool so I can see ecu data. What is bothering me at this time is the engine rpm's are reading about 400 rpm's lower than my tach. Idling around 575 rpm's according to the scan tool data but reading around 1000 on the tach. In my opinion it feels like it is closer to the 1000 rpm range but I don't have a way to check it at this moment. My question is where does the ECU get the engine speed? is it from the ICM or the CPS? If its the cps can the cps fail in a way that it still reads but reads low? I may be barking up the wrong tree and I likely am. but right now I'm trying anything i can think of. Any other suspected areas to check? Any scan tool data that would be more important than others? Any suggestion is welcome. Thanks Dan