My 2 cents-

1) Check that all the grounds are well connected.
2) Get a cable from
http://www.akmcables.com/
and hook it up to a laptop PC using datamaster or freescan. The cable will cost about $100. The SW can capture what the computer is doing and that might give you some insight. I am not an expert (I have just started using the tools), but the answer is out there...

 

dmoss69 ~ Car was totalled in 96, and it crunched the origional Opti I guess. The guy I bought the car off of had most of the new parts to go with it and some used ones. The opti was obviously in used condition. At the time when I put it together, I was just learning about LT1's otherwise I would have jsut got a new one then ( And long tubes ... There was NOTHING bolted to the engine, **** the engine wasnt even bolted down to the motor mounts, it would have been a heavenly LT install lol )

joebeemish ~ I dont have a laptop, however my cousin who is a mechanic said sat sometime he can try to hook up they're computer to it and see whats going on. He said they had trouble with a 95 TA though with the computer since its OBD1 with a OBD 2 connector ... but if all else fails, one of my uncles is a mechanic, and I know his Snap On computer works fine on my car so I could get him to hook that up to it sunday maybe


But if there are other things I can check before having to hook up to the computer, I will. Any help is greatly appriciated.

 

the intake gasket might be leaking

 

sounds a lot like the O2 sensors, doesnt do it when its cold and goes away at WOT.

 

**** UPDATE ****

Got the bitch good and hot, then my friend who is a mechanic sprayed the wires ( NOT OPTI ) With water, NOTHING, No change ... So it should be, 100% for SURE not the wires.

Its not throwing a SES light.

I checked my injectors today, with them hot, they Ohm out to specs ...

SO ... Plugs, Wires, Coil, Coil Wire, and Injectors are ok.

Thats leaves, Opti, MAP, MAF ( Which it SHOULD NOT be but someone suggested it ) and O2's ... I dont want to buy O2's and have it not be them. So im going to have it on a computer tommorow. My cousins garage, their compouter isnt a portable one, and it freaks out with Camaro/TA with OBDII connectors and an OBDI system. My uncles Snap on worked though so im hooking it up to that tommorow sometime I think.

Anyone with good directions on how to test the Opti, MAP, and MAF ?
Any suggestions are welcome, thanks.

 

I still say its O2's, but if you dont want to take good advise from people who know what they are talking about (shoebox) and someone who has had the exact same issues your having (me) then thats your problem. Good luck with it.

 

if its only during closed loop, its NOT the opti and its NOT the MAF. im betting on 02s - the scan should be able to confirm or defirm this.

 

It is your opti. I had the same exact symptoms, the car would run like a champ in open loop and as soon as I was at operating temp the car would miss fire and run like crap. Changed the opti and all went away!

 

if it was the 02 wouldnt' the check engine light be on?

 

Not always, in my case mine wasnt.

 

Im not doubting you or shoebox ... I fully intend to have the O2's checked out tommorow on my uncles Snap-On computer ...

Im jsut asking for more advice from otehrs who have had similar problems. I dont want to run check the O2's and if its not them, have nothing left to fall back on and check next. Sorry if I came across that way.

In a way, I think its the O2's cause it wont do it at all when its in Open Loop/floored. So it almost has to be sensor related.

But at the same time, I cant help but ? the Opti because it could have 150,000's miles on it, its from a different car, used, no idea how old it is, cause the origional got rushed back in 96 when it was totaled.

 

my buddies was running pretty crappy like yours and his set for oh id say a lil over a year and he had some bad gas in it and mixed it with good gas and it ran like crap till i drained the bad out and put new in, it ran alot better, but his plugs are screwed now

 

***UPDATED AGAIN***

You guys are right, its the O2's ... Put it on my uncles Snap On computer today and checked some stuff out ... The car was pretty hot from the ride over, lots of hills and it was a 20 minute ( ride ). Parked the car, the engine was off 5 mins if that, before he hooked his computer up too it. It took OVER 7 and a half ( Last time he looked ) minutes before it went back into closed loop, and that was with it hot, and lots of revving ( Sign of bad O2 )

Duringthe time it was hooked up ... This is what was recorded ...

Left 02' - Open Loop under/around 100mV ... When it finally came into Closed, It jumped all around like it should between 100mV and 900mV

Right 02' - Open loop & Closed loop, it stayed right around 550mV +- 5mV No matter what, idle, revs, driving. It didn't like to flucuate at all, and NEVER went above or below 500mV to 600mV ( Actually a narrower band then this, even once it would FINALLY kick into closed loop )

It didnt reach closed loop for at least 8 minutes, and the coolant was at/around 225*

Spark advance was 21* at idle (900+-RPMs M6, Open Loop) and advances to 37* at 3500RPM (Is this normal, I donno what it should be at/around)

MAP read about 1V at idle and would fluctuate depending on throttle ( So its fine )

MAF read 9gm/sec @ idle, works fine when throttle increases/decreases

Left BLM 125, Right BLM 108 @ Idle ... I know, im stupid, but what the hell is BLM? I jsut remember hearing ppl mention it on the board when concerning tuning and stuff, and wasnt sure if it was normal so I wrote it down jsut to be sure.

 

Left BLM looks good, right one looks terrible, which comes from the O2 sensor.

Get yourself a new O2 sensor and watch them. The blms should hang around 128.

BLM---block learn memory This is a unit that the PCM uses to control fueling. (This is the worst definition in the world, but that is it)

 

Ide have to say it is in the ignition as well and not so much fuell related Heat is an engines worst enemy correct me someone if im wrong but coudnt it also be a module acting up when it gets hot?