Just purchased this 94 Max GXE with 190K miles and have been trying to get it on the road. I guess I need to give a full recap of the situation. Got this car in July. Replaced one injector right off the bat and followed up with a complete tune up as well as two more injectors a month later. Ran great for a while until MAF went bad (tried the spray cleaner, didn't work). Two weeks later the number 2 injector connector came loose. At least the Plenum removal is down to a science now. After finally ensuring the plug will stay in place and reassembling everything, again, I could not keep the car running. Apparently that's when the IACV decided to crap out. Replaced it, set the adjusting screw by turning the it all the way down and back out three complete turns, cleaned the TB and entire IACV valve with TB cleaner. Also tested the TPS and reset it using Ohm meter. It is now set fully counter clockwise because that's the only way to get the engine to idle. So now the car will run smooth as silk at start up but after three minutes it misses and runs like the timing is way out. I have been through so many of these post they are starting to run together. I am not a complete moron but definitely not Mr. Goodwrench either. If anyone can please help me out here I would really appreciate it.

 

Have you checked your coolant temp sensor along with hows the O2 sensor? Sounds as if your having a hard time when it goes into closed loop. Also I noticed you mentioned you replaced 3 injectors. Good now you have 3 more to go to rule all of those out.

 

Ohm checked all injectors (again) when I replaced the last two, checked out good. Also replaced the coolant temp sensor since my temp gauge is not working...only to find out there are TWO seperate sensors in that system. Temp gauge still not working due to corroded wire I found last night. Go Figure.

 

Injectors can ohm out to spec that doesn't mean that they are physically ok. Ohming can't check busted o-rings or clogs.

 

Car was running very smooth before the #2 injector lost connection. The open injector circuit code (51) has not reappeared after fixing the pigtail.

 

How was the condition of the sub harness for the injectors under the intake?

 

Other than having to use an O-ring to secure the #2 connection (lock tab a little loose) the harness was fine. Went out and started it again this morning before heading out to work and it started running really rich after it warmed up. Good friend of mine says I need to test the MAF even though it is new.

 

Check the ECU from the passenger side to see if any code is being reported. Turned out mine reported code 12 which is the MAF and was replaced; now running much better. You can search how to put the ECU in diagnostic mode and then Google the codes if any.

 

Have access to a good scanner and no codes are being read.

 

I'm strongly leaning more towards your car having a vac leak. I was thinking a little towards it in the beginning, but the more you go on the more I'm convinced you have unmetered air entering your system.

 

One of the ASE Gurus I work with had a chance to look it over with me last night. He went over everything I did and finally decided to check fuel pressure. Did not have any. So we snatched the seat out and pulled the cover off the fuel pump. After the third screws was removed we heard air being sucked into the tank. We turned around and started the car and listened to run nice and smooth. Not sure if it is the cap, filler neck or vent tube. He told me that I had just witnessed the appearance of a very rare mechanical white elephant. Either way I am very greatful for all the help.

 

It might be the cap. Aww Ima be so upset if I have an issue as such after all I've been thru.

 

Trust me...it's a relief and one of those f*#k me moments combined. Ran the car without the fuel cap and started doing it again. Will be removing the filler neck tonight after work to look for soft hoses. Hopefully that will not be too $$$.

 

Naw it shouldn't be too expensive.