Still having problems with my 92

[whiteman_01]

Ok, For the last few weeks my car has been acting weird. Sometimes right around 5500-6000 rpm's it will start to break up. I have replaced the following with known good or new parts.

Fuel pump: new
Fuel filter: new
02's: new
55mm maf: known good
TPS: known good

Plugs and wires are within 5000 miles. When i would run codes i would come up with a 519 and a 556. The 556 is for the fuel pump circuit failure. A friend of mine found a schematic on how to test the IRCM and the high speed fuel pump relay tested bad.

So i picked up a good (tested) IRCM and put it in, and i am still having the same problem. The IRCM i took out was a "J" and the one i put in is an "M".

I realized that this started happening right after i changed the t-stat. When i put it back together i put one of the wiring bundles under the t-stat housing. These wires include the MAF, the TPS, and something else i think. I relized that it was tight against the bottom of the housing when i was putting it back together, but i didn't think anything of it.

One more thing, last night when i put the new IRCM in, my brother heard what sounded to be a small vac or intake leak but we could not pin point it.

Sorry for the long read, but thanks in advance for any ideas.

 

[SHOtime2511]

the vac leak could be causing the problem.
also check you ignition system grounds,the strap on the rear of the intake,and the bolts on the crossover tube

 

[SuperHO]

That bundle of wires is supposed to go over the top of the thermostat housing...or at least it does on mine. It's possible you might've pulled something loose doing that. As far as the vaccuum leak, we ALL know how to test for that....starter fluid and spray the living shit out of the running engine. If it bogs down, that's where the leak is. when you changed the thermostat, I'm assuming you pulled the TB off....did you put the gasket back on? I've been guilty of that more than a couple of times. Worth it to check.

 

[whiteman_01]

I did not take the TB off to do it. All i took of was the tube that goes between the TB and the air box. I wonder if i mealted one of the wires? I am going to go pull it apart now since i finally have time to.

Also i fogot to mention that i have checked and re-checked all of my grounds.

 

[whiteman_01]

UPDATE:

I did find while taking the intake off that one of the 10mm bolts was rather loose. I doubt thats the problem, but i will find out.