85Special

Ok so got an 85 iroc with a motor swap to a 350. Ran like a dream when I first got it. It sat in storage for 10 years and have been driving it for the last 2. Sense I have had it back I've been fighting one thing after another failing... Naturally... No surprise I expected as much.

I have replaced:
Cap
Rotor
Distrib module thing can't remember name
Coil
Wires
Plugs (accell header plugs .044 gap) 5 days old
Intake plenum gaskets
Fuel injectors ( 22lb Bosch III's )
Fuel pressure reg.
All vac lines clean and kink free and new
O2 sensor
MAF new reman installed today
TPS (.55v - 4.58v wot)
IAC
IAT (pulled off open probe installed solid probe not sure if that's a good thing)
Fuel filter
Have 2 small breaks in the exhaust gasket... Next on repair list.
Fuel pump not replaced 50lb static 35lb at idle.
Computer replaced stock 87 350 tpi set up
Hooker block hungers no smog pump into a 2 3/4 inch exhaust. Otherwise stock 87 set up.
EGR temp sensor new.
EGR has not been replaced, passages seem clear, but i can't seem to get the damn thing off to replace it. Diafram is good... Seems ok

I'm running rich as hell and feels like a v6. I don't get it... I passed emissions in January.

riche

"Have 2 small breaks in the exhaust gasket... Next on repair list."
upstream or near the O2 sensor?
If so does it run Ok until it warms up?

rusty vango

85s have a different computer set up than the 86-89. MAF is also different(do not buy a re-man from cardone!!)also MAF cars are relay sensitive,you MAY have a mis match of components,which IMHO could be your problem

85Special

I'll double check the MAF part #. I may have goofed and bought it for an 85 the rest of the system is 87. Also come to think of it the exhaust leak is on the o2 side. It does run better cold. The MAF is cardone, I work at autozone and it was on the shelf so I snagged it... Still regret it. Any ideas on a good one?

riche

Check your o2 voltage when the car is up to normal driving temp. See if it is showing a false lean voltage due to the leak.

85Special

Well hell I was thinking when I got the MAF. It is for an 87 so that leaves me with relays and o2 to check. With the new MAF it's better but it loads up if I'm idling too long. so I'm gonna give it a once over tomorrow and see. I obviously have a misfire somewhere, it lopes a bit at idle as well. If I replace anything with the MAF relays I'll go to "oh really's" not sure I can fork out $450 for a new MAF right away but it's on my wish list.

vetteoz

iTrader: (13)

Have you pulled the codes to see if you have any faults showing?
Guessing and throwing parts at a problem is a good way to waste time and $$$

85Special

No codes at all, thus my confusion. All the parts in the list is what I have replaced in the last 2 years. The bulk of it was 4 months ago when I was registering it in AZ and had to pass IM. Very little of the list was actually replaced for no good reason. Car sat for 10+ years. I did get 22 and 32 but I caused them to trip messing with the TPS and got code 45 before I swapped out the MAF.

riche

If you don't have a scanner software that will let you see data in real time. Try to figure out what type of O2 sensor you have. It should be a narrow band type. Try to search around and figure out the wiring. One of wires will be the 1 volt signal wire. Use a volt meter to read the voltage. It should be all over the place switching very fast. Try to see if it stays primarily below 0.4 volts.
0.1-0.4 = lean 0.4 to 1.0 = rich
If the voltage stays consistent and doesn't change alot that could be an indicator of a bad O2 or if it stays consistent bellow 0.4 volts I would say that the exhaust leak is creating an excessive false lean condition. BC the ECM should try to adjust the fuel trim to correct it so it will just keep dumping gas into the engine to try to offset.
Or the ecm is dumping a bunch of gas in there and has made the adjustment. In which case you will see the voltage hovering around 0.4 volts. If you see 0.4 volts and still think it is rich I would say that the ecm has made the adjustment to offset the leak. That is why it runs better in open loop till it warms up. then once it goes closed loop the ECM throws way to much fuel at it.
The best thing to do would be to have the ability to turn off closed loop and test the O2.
I wish I knew more about third Gens specifically to help you with the O2 wiring. I have been lurking on the boards trying to learn about my aftermarket setup I retro fitted into an old truck.
Try to fix that leak, It can really do a number on an O2 reading. Even a small one.

Hlvo13

story of my life, i spent over a year playing the guessing game, nothing a good paperclip cant fix...and its way cheaper then all those parts you may not need

85Special

Well the leak was not a small one. blew out the bottom where I couldn't see. Got a better set of gaskets this time. They blow again I'm going to metal gaskets, but hopefully if I get into a habit of tightening/checking the bolts weekly I shouldn't have to. Damn headers!

85Special

Much better. took it for a drive and it was loading up and falling all over itself... let it heat up and burn off the plugs which I'm sure we're a mess and it's getting back to its old tire burning self. Got a few clouds of crap out of it and it started to idle better. I let it run for a bit than shut it down and re tightened the header bolts. Going to let it cool off and check the plugs and see where I'm at but I'm hopeful.