Search the Community
Showing results for tags '2.5l troubleshooting'.
Found 4 results
Here is 1987-90 Jeep YJ Wrangler and Jeep XJ Cherokee/MJ Comanche 2.5L TBI diagnostics information in PDF form. The first document includes all sensor and switch tests plus adjustments that affect engine tune, idle and reliability. Wiring schematics and ECU pin locations, test plugs and diagnostics included. Jeep 2.5L TBI Complete Diagnostics-Sensors-Switches.pdf Jeep 2.5L TBI ECU Inputs and Outputs.pdf Jeep 2.5L TBI MAP Sensor Test.pdf Jeep 2.5L Timing Chain and Tensioner.pdf Jeep 2.5L Valve Timing Check.pdf Jeep YJ 2.5L TBI Sensors and Pinout.pdf YJ Wrangler 2.5L TBI Wiring of WOT to ECU.pdf Jeep YJ 2.5L ISA Wiring Diagram.pdf 1987-90 2.5L TBI Intake Manifold and Sensors.pdf 1987-90 YJ Wrangler 2.5L TBI Emissions System Parts.pdf YJ Wrangler Fuel Filter and Guard.pdf 2.5L TBI ISA Motor Adjustment.pdf Used in conjunction with the many forum exchanges (search under "All Content" and "2.5L TBI" in the search box), plus the Jeep 2.5L TBI troubleshooting article at the magazine website, this information will help solve your Jeep YJ Wrangler or XJ Cherokee 2.5L TBI troubles. In references, the Model 81 is the Jeep YJ Wrangler. The Model 60/70 is the XJ Cherokee and MJ Comanche Pickup. Moses
Sinisterwillys1940 posted a topic in Jeep® YJ Wrangler, TJ Wrangler and LJ WranglerI put a new 2.5l into the jeep and it only has 400 miles. It was running great till suddenly the issues popped up again. I hooked the scanner up and saw that the short term trim was ridiculously high. Its reference point at idle is 128 and its running at 180. The long term trim is at 109. the injector pulse is 2.0. The o2 sensor was reading no higher than 500mv.
Lowell posted a topic in Jeep® XJ Cherokee, MJ Comanche Pickup and Grand CherokeeI'm at my wits end troubleshooting my lil 2.5L engine. I googled and found your page from about a year ago. 1990 jeep wrangle 25l engine timing. Today I thought about timing. It misses, like running on only 2 cylinders when at low speed and and only pulling slightly. As I move into mid and upper rpm range it stops missing. I still do not have much acceleration but at least it stops missing. I've check and/or changed every sensor it has. TPS is only rough since I have not gotten my laser tach to work yet. In checking fuel I have only 10 psi so I know that's a problem. This started about a month after the SMOG guy changed the O2 sensor to pass smog. I've check the voltage when hot and it's within spec. I also had massive exhaust gasket leak so I cleaned the surfaces and replace the gasket. I'm a machine mechanic from way back in the Navy so I'm not just a new mechanic. I just can't quite figure this one out. I'll check timing tomorrow. Lowell
Lowell posted a topic in Jeep® XJ Cherokee, MJ Comanche Pickup and Grand CherokeeThanks for the engine information. Ok .... update for today. I'm really not finding a vacuum leak and before I build a smoke machine there's been this gnawing in the back of my mind to check the valve timing. I found this pdf manual http://oljeep.com/JeepEngines.pdf and on page 63 it tell how to check valve timing. So I removed all the plug, it was easier to rotate by removing all the rocker bridges, set up a dial indicator on the #1 intake push rod and checked .... Hmmm the dial moved .010 but I don't see the index mark anywhere (????) ... oh, there it is 3 inches to the left, or 3 inches BTDC ... really???? Guess I'll pull the timing cover and check it out.