After obtaining three 220 uf 35v capacitors and returning home and removing ecu and preparing for capacitor replacement I see that one of the capacitors is a taller 470 uf 25v. Has anyone run into this? Is it ok to use the 220 uf 35 volt or do I need to get a 470uf? Please and thanks.
I ran into the same thing while doing mine, I went to radio and picked up the 470
In my opinion I think it would be a bad idea to replace it with a 220
Ya, heres what I did. I tried replacing just the two 220uf capacitors, plugged it in to jeep...no go. So then I drove the 60 miles to town and picked up a 470uf and soldered it in. Hooked it up and...................success, fuel pump cycled and it fired right up. An awesome fix. Thanks to the original poster of this fix and contributers.
470uF is a filter cap freq response that moved the effective reactance of the cap to the 1Mhz or the AM band. It's just a minimal change for the frequecy cutoff of the cap. The voltage is more important in the application it's being used.
This thread is very helpful. I have all the symptoms, followed sentinal02's link, everything is pointing at the ecu. Gonna give this a try as soon as I can make it to Radio Shack. I'll let you know how it goes, I'm doing this on a 93 zj.
Just out of curiousity would this fix my problem no fuel pressure and replaced pump, filter and pressure regulator with no fuel pressure and only like 5 volts at the harness fuses and relay are good. No spark but have power to everything an it's all been replaced except ignition itself?!???
Does your check engine light come on when you turn the key? If the light does not come on and go off when you cycle the key on then you have the ecu issue. If it does then your problem is something else.
I own a 93 grand Cherokee and have the problems with the chatter in the fuel pump/auto shut down relays. And after reading this original post i checked my PCM capacitors and clearly saw a bad cap. But the cap I have is a brown 220,uf 25v and after calling radio shack they only carry the 35v is this really ok to go up in size?