93 z34 with problems. PLEASE HELP

[jdellinger1980]

I have replaced almost every sensor in my z34 and it still has problems staying running and stalling when it comes to a stop and going around corners and just slowing down to a low idle it dies every time when its in park it idles just fine for about 10 to 15 minutes and then dies. I just read on another forum about phantom stalling and it matches my problems exactly it also said that I could find some kind of hard to find injectors on this website that will fix my problem if you agree or know where these injectors are please help me out thanks so much.

[Mole1333]

Have you done proper testing? Fuel pressure, vacuum...etc. I would be more worried about that first. And as far as almost every sensor...which ones have you done and which have you tested? Did any fail tests or are you just throwing parts at it? I'd also check the the catalytic if it has one still. You will get more responses if you post this in the DOHC Forum.

[jdellinger1980]

Have you done proper testing? Fuel pressure, vacuum...etc. I would be more worried about that first. And as far as almost every sensor...which ones have you done and which have you tested? Did any fail tests or are you just throwing parts at it? I'd also check the the catalytic if it has one still. You will get more responses if you post this in the DOHC Forum.

Hey thanks for the reply, here is what I have replaced I had the codes checked and it said the IAC was bad so I replaced that, I had the old IAC checked it was not bad so I put it back on and then I changed the plenum gasket because the mechanic said that an IAC code could be a bad plenum gasket. I also changed the map sensor cause the piece that it attached to was broken and I went to pull a part and bought the whole assembly, I have replaced every vacuum hose I could find, vacuum modulator valve, I had the fuel pressure checked when it was diagnosed at an auto electric shop. So I was a little wrong when I said I replaced every sensor just a few and yes I have been just throwing parts at it because I have heard so many different things that it could be, and how do I check the catalytic converter and would this register fine on the obd test if it was clogged or something wrong with it and last of all I thought I was on the dohc forum and if not which one is it. Thanks for any help you can give me. Joel

[bszopi]

last of all I thought I was on the dohc forum and if not which one is it.

It was previously in the Member Section, but was moved to the DOHC section.

[jdellinger1980]

It was previously in the Member Section, but was moved to the DOHC section.

Thanks, does it really matter which forum its in? Just wondering Im new to the forums.

[bszopi]

A lot of people don't read the member's forum, so asking a question in there usually doesn't get much coverage. Having it in the appropriate will result in a better chance of someone will read and be able to answer it.

[Incydowt]

I experienced the same problem with my 3.4 Cutlass, I did the IAC, MAF, to no avail, turned out that I had a lazy O2 sensor that wasnt tripping a code, If you have access to a scan tool I would watch the O2 (upstream) for slow readings, I put that in the car was fine... Or you could also just pelace it considering it probably older than dirt anyway, I had the same prob, this is my fix, I am also a trained technician, so yeah funny I know but try it. I would venture to say I am 75% sure its your prob

[jdellinger1980]

thanks

Thanks for the reply This thread has been up for a while and Ive had many solutions and someone told me about phantom stalling and told me I had to put a bigger injector in and I did this and everything improved for about a month and now it is starting to do some of the same things again. So my question is where is the o2 sensor at and do you happen to have an idea of how much one cost. I can do pretty much any of the work that needs to be done to my car I just need to be pointed in the right direction, thanks for the response.

[pocket-rocket]

~$50 and it's in the rear exhaust manifold. The O2 sensor reads the exhaust to tell the ECM how the engine is running, so you really confused the ECM by putting larger injectors than it was calibrated for. I would put the originals back in, change your O2, pull the ECM fuse (for ~30 seconds) to reset the ECM and let it relearn.

[jdellinger1980]

I cant put the old ones back in because when I took the old ones out they were all cracked all the way up the side and were no good, Ill just have to find some more stock ones.

[pocket-rocket]

I also forgot to add. Our DOHC injectors have a different spray pattern than normal pushrod/ohc engines.

[Incydowt]

The only Injectors I have heard work are out of the chevy 4.3 liter, They are a 45 lb/hour injector with the same spray pattern, the best way to get at the o2 is to pull the plenum and get it out from the top,

[jdellinger1980]

injectors

I guess I need some stock injectors if you know anybody thats got some please let me know. Thanks

[RedZMonte]

I think i still have my stockers in the garage... Let me look when i get home. I will sell them cheap... they came out of my '95 Z34 w/ ~90K miles. I swapped them out with the turbo setup. they worked flawlessly untill the day i pulled them. I changed my fuel filter and ran BG44K on a rutine basis so they should be perfect.. I would suggest new O-rings when you put them in.

S

[mrsleeve91]

You really should check the fuel pressure, and pressure regulator. My Regulator failed and the fuel traveled up the vac. line, cooked the map sensor. The fuel was pooling in the intake and doing very similar stalling. Also mine had a difficult time starting (Duh- wrong fuel pressure and tons of raw fuel...) Just wondering if you were also having that issue.