I have a 95 3.8l v6 it is misfiring really bad and having power surges. In the last 3wks I have replaced the maf sensor, the iac, erg, plugs, wires, fuel filter, vacuum lines, icm, and the crankshaft sensor. Nothing seems to be helping and I am at a complete loss for what could be causing the issue. I've had it in the shop twice and both times they said it was the icm. $1500 later it is running even worse than ever any input would be greatly appreciated thanks

 

Is your check engine light on? Because some of those things you replaced would have tripped the light if they were bad. Get the car scanned for codes before you continue to throw more needless parts and money into it.

 

^ What he said. Even if the SES light isn't on, codes may be stored, so check that first. Personally, I would have checked the spark plugs, wires, and coil pack before I spent money on any parts. ICM can be checked at local parts store usually.

 

Codes have been checked mostly throws anti theft and low circuit maf. At the shop it was throwing p0102, p1626, p1651, p1655, I had the icm checked at parts store and they said it was still good, so I took it back to the shop and they said even though it shows good it can still be bad idk replaced it anyway hoping like crazy it would be the issue but it wasn't. Changed the o2 sensor today still idles erratically and car stalls and shuts off. I've had the fuel pressure checked and it was running rich at start up but then lean when it idled out fp was at 55lbs. The ses light has been on which is why I've tried to narrow down the issue. When I replaced the crank sensor ( it was cracked) car ran great for a day was at about 90% had power and a** back but next day was running worse than before. Honestly don't know what else to do this car is my daily driver and lately it's rather embarrassing driving it. It's starting to jerk and sounds like snapping down by the u joints and reverse is starting to slip I love this car and I don't want to lose her lol thanks for the replies I hope this info helps you understand my issue a little more

 

The MAF code can cause poor running, unplug the MAF connector & see how it runs. The engine can run OK with the MAF disconnected.

 

recheck the crank sensor for damage and look to see if the wires or connectors are damaged. you may have moved or repositioned something that is close to failing or not connecting right so check wires and connectors in that area.

 

catalytic converters are clogged??

 

The MAF sensor connector is a common failure point and they are sold in most parts stores. Coils are also common failure point. With the syptom codes you have and the work done so far it seem like you may have atleast two issues. Another possibliity is the PCM itself is failing.

If you want to test your coils get an inline spake tester. If I had a low voltage Maf error I would just solder in a new connector if it has not been done before.

 

Ok so the cat is still good and I disconnected the maf checked the pigtails with a voltage meter on all sensor points and got readings so that's ok however the car did run better without the maf hooked up so I'm going today before work to get another one. The guy at advanced said not to run it without the maf hooked up but I inquired why it was running better without than with and he said it should be the other way around. Idk just know it's running better without. Ran it yesterday and wiggled wire harness there was no change so I don't think its a wiring issue. Will put new maf on and see how that goes. Will let you guys know. Have coil packs ordered and can get PCM for under $200 just in case. Thanks for all the assists really appreciate it.

 

Just a FYI most guys that sell parts at the parts store are clueless. I did say most. I have gotten a good laugh a few times overhearing "advise" they have given. In one case I interruped becasue the advise would have damaged the motor. It was something about using a hammer to remove a vibration damper.