Car has been running horrible, stumbles, missing and hesitating. My first thought was it was only running on part of the cyclinders.

Heres what I checked and the results.

1. With a heat guage/gun took temp on header close to head
2. While car was running I unplugged injectors one at a time.

Results on each cyclinder:

#1 Temp 500. With injector wire unplugged car died
#2 Temp 450. Injector pulled car stumbled/running rough
#3 Temp190. Injector pulled no change in idle
#4 Temp219. Injector pulled small notice in idle change
#5 Temp 200 Injector pulled no change in idle
#6 Temp 445. Injector pulled small change in idle
#7 Temp 254. Injector pulled No change in idle
#8 Temp 400. Injector pulled small change in idle

Obivously we have problems with cyclinders firing. My question is where should we start in figuring out what the problem is? Cant pull plug wires while car is running unless I want my arms burnt to toast.

Thanks

 

Have you checked the fuel pressure? Have you scanned it for codes? A scanner with GM enhanced parameters capability can pull the misfire count by individual cylinder. All of these might point you in the right direction.

 

It looks like cylinders 1 & 2 are keeping your engine running. First, check all your plugs and wires, or just change them if they are ancient. Then, if that isn't it, you will have to swap injectors around a bit and see if the problems follow them. If the answer is 'yes' then either get new ones or send them out to get cleaned. If the answer is 'no' then you will may to delve into your optispark distributor and see if it is infected and can't make spark. If it is at all possible, you might want to hook up a laptop to your car and see if everything is working because if you lose a temp sensor or MAf sensor is fubard or something and the engine is flooding itself and killing the plugs, that can make it run bad. So you got a lot to look at here, but start with the basics and see where that gets you.

 

Ok, thanks for the advice. I'm shopping for scanner now. Can you tell me what size injectors I should buy if that ends up being the problem. What brand are reilable and where is the best place to buy?

 

If it turns out injectors are your problem I'd find a set of stockers or have yours rebuilt. There are TONS of stock ones on the forums nowadays.

 

Stock ones are ok for my set up?

 

Stock injectors (programmed as 24.9 #/HR) are good for 360HP at the flywheel, while still maintaining ~85% duty cycle. Unless you have ported heads that are not shown in your signature, you should be OK.

 

My heads and intake both have been match ported. Forgot to udate my sig. Also I got a scanner from orielly's the one you rent. It is a OBDII compatible. When I hook the scanner up and turn the key on the scanner acts like it is not hooked up to the car. Scanner or cable problem? or my possibly my pcm fried? Also the car won't start anymore.

 

Ok, so I found out if the ciger lighter fuse is blown it wont power the OBDII conector. I checked the fuse which is # 11 and its good, but the cig lighter doesnt work. Also found out the # 16 pin on the OBDII conector on the car should be hot and it's not. Trying to hook the scanner up but no power to the plug. Any ideas? I'll start by looking at the wires at the connection and going to cig lighter to see if all is well. Any other ideas would be appreaciated.

 

When you get around to updating your signature correct your overbore to 0.030

 

Will do injuneer. Also forget my last post, I finally pulled my head out long enough to figure out there are two fuse boxes. Replacing the fuse and hopefully I will have some codes to post in a bit.

 

Only code I could find was a stored code P1222 (injector control circuit intermittent) I have a fuel pressure guage but not sure where to hook it up, and the car won't start.

 

there is a schrader valve in the fuel line just behind the plenum, it barely sticks up and most likely has a plastic cap on it. make sure to tighten the tool to this valve with your fingers and put a rag below it if you can. you need 41-47psi of pressure.

 

http://shbox.com/1/fp_reg.jpg

 

Ok, what about the code p1222