Hello everybody,
Bare with me as this is my first post... I will try and make it as brief and direct as possible

So, basically I bought a 1990 IROC-Z with a 305 TPI engine... When I bought it the guy before me had the EGR valve disconnected (lines were taken off and plugged with a screw?). Here in Canada, we have emissions tests and basically they told me I needed to fix the EGR and the Oxygen Sensor to get a pass (as it obviously failed, meaning I couldn't drive it more than 10 days). Long story short, I bought a new EGR valve and O2 sensor, replaced both and hooked it all up, and has since passed the emission test.

However after directly doing so, the car constantly stalled and was not running well at all... I pulled out all the plugs and they seemed to be covered in oil, so I cleaned/gapped them and it seemed to run better (was at least drivable)... It does however seem to stall a lot; I could be coasting at 60 km/h (40 mph) and the engine just dies. It also stalls a lot when I put it in reverse and tap the gas a bit to move backwards.

I noticed that the engine idles rather high while in Park or Neutral (about 2000 RPM on average, sometimes hitting almost 3000 RPM at times) and drops when in Drive or Reverse (about 500-800RPM)

I also noticed that the car seems to stall A LOT more when I run it a bit rough (accelerating quickly, often).

Another issue that is most likely related, that doesn't happen too often (have been driving it for around a month and it's only happened twice). The engine will seem to lose all power, clicking on my Service Engine Soon light... the car then doesn't go anywhere really... it seems like it is misfiring and the accelerator to the floor gets me no where... after a while the light goes off and power is restored (about 15-60 seconds)... not sure why this happens...

I ran a diagnostic tool on it and it is only giving me an error code 33 (which says it’s the MAF or the MAP voltage too high during idle, but that it may also be caused by high idle/misfire)

I did some research and came to the conclusion that the 90' IROC MAF was replaced with a MAP system.

I'm not entirely sure where to start with this one... as I'm not sure if I should replace the MAP or go a different route, such as a tune-up and what not...

Also, almost forgot to mention… the car seems to “surge” at times when I accelerate. The car pulls along causing a rough acceleration. It’s hard to notice at times but definitely is there. It almost seems like it's misfiring, except not as rough.

Given how I just got the car I don’t know too much about the 305 TPI engines (at least not yet), which doesn't help me with a starting point at all... hence me seeking advice from the experts online...

Hopefully I provided enough detail and information about my problem, I tried to keep it short but it seems to be a long read...)

Thanks for reading, and hopefully someone can point me in the right direction

ANY help/advice is GREATLY appreciated, thanks again!

 

Well for starters since this stuff started after you installed the EGR and the O2 sensor lets start there, primarily the EGR valve. How exactly did you hook it up?

 

Thanks for the quick response, and apologies for the late reply (out of town for a while)...

Well, I am not ENTIRELY sure if it was running bad before the EGR hook up, as I didn't drive it very much prior... I do know it is doing it a lot now however. It never stalled before on me, but I think it did idle higher than normal...

As for hooking up the EGR... I basically followed the manual I had (Chilton I believe)... Took off the intake, took out the EGR... put the new one in, put all gaskets back in with required torque, and connected the vacuum hoses according to a diagram on my hood (also found the same one online)...

I can't see where I may have went wrong... I also am not sure if the EGR that was in there was broken or not, just replaced as I had it all apart. This leads me to believe why he had the EGR disconnected in the first place (something wasn’t working properly).
Not sure where to begin, may take it to a diagnostic center and get them to tell me where to start... figured I'd start here though and get some expert advice...
Thanks again

 

Well how did you hook up the vacuume lines? The reason i ask is although it seems pretty strait foward there is one place i can see getting confused and thats the EGR solenoid as it has 3 connections but only 2 should be connected and the 3rd left open to vent off the vacuum to the the EGR when its dissabled. Also check for vaccum leaks.

 

Ah I see what you mean... I will certainly have a closer look and let you know how I have it connected...

As for vacuum leaks, how do I go about checking those? I know I've had it done before, but had a shop do it... is there any way to do it myself or do I need to bring it in? Such as any special tools, machines or methods...

Thanks again

 

I brought my 305 tpi in 2003 to english town,, with just a bunch of free mods and an exhaust and ran a 2.3 60ft with a 15.6

a year later i added an intake,, power pullys and 3.73 gears with subframe connector and ran a 1.9 60ft at 14.9

ive since added a lot more(350) but restored her to prestine condition so i dont run her anymore..

 

my bad .. wrong thread apologize about that