i was speakin to a friend of mine who told me that i might have overheated the caps if i took too long to solder them...one of them did take me a while...so im gunna replace again and cross my fingers thas the problem...ill let u guys kno wat happens...but just in case...wheres the cheapest place to get another ecu? Other than salvage yards? Cuz all the ones around here dont have any wranglers in em....i called around...
ok the ecu's definatly not gunna work i am now officially in the market for another one. does anyone know what year ecu's will be interchangeable with my rig? also, can i use one with auto trans even tho mine is a manual?...
Has anyone other than Anonymous6915 tried this solution with the 4.0L? I have the same exact symptoms, but have yet to try leaving the key in the "on" position to see if it will start after that, and it's sitting at a friend's house at the moment since I had the problem when I went to leave to go home. Also, If I do have to replace the computer, I have read that the ECU from a Cherokee with the 4.0L will fit my YJ and any other 4.0, regardless of standard or auto tranny as long as it doesn't have cruise control, is this true? Anyone else have any similar problems with solutions? Help is much appreciated, it's my DD and need it back on the road ASAP
"If the ladies don't find you handsome, they should at least find you handy" -Red Green
I've been encountering the same symptoms. 1995 YJ.
I put in a new distributor (complete) last night, I installed a new CPS on Christmas eve, previous to this I had new plugs and wires, new starter when it first started..and so on.
Will try this next.
Leaving the key and listening for the fuel relay to start click and start has become a habit in the two months.
Both the troubleshooting tips to determine if the ECU was the problem and this thread to fix the ECU worked awesome. I can't thank you guys enough, this forum is a life saver.
I have a 91 YJ 2.5 4cyl. The only thing I noted to be different on mine was that I needed (2) 220 uf's and (1) 470 uf. I'm not sure why mine was different (and in different locations than the photos), but Radio Shack had them all it it worked great.
can you tell me if this is the problem on mine? when i try to start, the fuel pump primes and the check engine light comes on, but the started does not engage at all. once the key is in the ignition for a while, it will evantually make a clicking noise when i try to start it but will not start. if i leave the ignition on for a while after that, it will evantually start. do my problems fit the ecu repair? thanks
i dont think its the same problem...this is to address that your check engine light does NOT come on...but if your getting it comming on then ur ecu should be fine. sounds more like a problem with the starter maybe a wiring problem? somone else who knows more will chime in im sure...
Thank you to all that posted on this thread !!!!!!! You guys are amazing . I had this problem on my 95 YJ Wrangler. I replaced the capacitors with the Radio Shack 220/ 35v capacitors and it's running !!!! My friend in electronics ran a test on the caps and found one reading 25 micro ferads when it should be at about 220 . The other 2 were pretty close to the specs. He told me these are like little liquid batteries that should only last about 10 years. There are caps. that are made of a dry chemical that should of been used for this application and has a life expectancy of 30 years. Firestone wanted $650 for the computer (ECM/ ECU) and $150 for labor . Ebay wants $250 for a rebuilt computer. It took 10 min. to take it out of the Jeep. Took about 1/2 hour to repair the board. This thread was right on the process. It cost me $6 at Radio Shack , some time, and I threw alittle cash to my friend. Thank you to all !!!!!!!!!!!!!
Another Huge THANK YOU for this thread. I have a 95 2.5L 5 speed and it died the other night. It would start occasionaly for about 15 sec then die and not restart. I checked the fuel, did a complete tune up (knowing it MUST be the cap or button). No good. Then I found the thread in hear that took me through the ignition checks and determined that the CEL was not coming on so I hoped it was the ECM. After a $6 trip to Radio Shack and about an hour replacing the caps, the CEL came on and she started right up time after time.
So I've been having this same problem for a year but it never failed to start until last night after I played hockey til 12am and had to work at 7am and was 45 miles from home. While I waited for my wife to come pick me up I searched this forum from my blackberry and came across this thread. I bought the 220uf capacitors and 1 470uf just in case. I trekked back out to the rink with my tool box and capacitors. Radio Shack only had capacitors with axial contacts so if you use these make sure the arrows point to the same side as the stripes on the oe ones. $1.39 ea for the capacitors, $4.50 for the silicone. BWAHAHAHAHA to those selling used and reman ecu's. Anyway, an hour later the jeep fired right up and everything seems perfect. Count this as another huge THANK YOU from me.