Diagnosing problem

[Mr. T-Type]

I was driving home a week ago and when I boosted (basically stock), there was a pop and my car started coughing a little wihle cruising. I pulled over at a gas station and gave anything a once-over and didn't see anything. No leaks, no smoke, no cracks, no cracked hoses, nothing.

I drive it home and the coughing and stuttering gets worse. As I pull into my driveway, the car stalls out and won't start again.

I figured this would be a cracked IC pipe and that caused the spark plugs to foul out. I replaced the plugs and wires then took the intake apart and couldn't find anything except a small amount of oil on the end of the IC .

Anything I might have forgot about? I don't want to start it up and drive it for a few minutes then have to go my spark plugs again or hurt something if that wasn't the problem.

 

[TT/Ameasap]

I think when car pops under boost it is running lean. Did you Check symptoms of blown head gasket?

 

[JToups386]

What are you referring to when you say "cracked IC pipe". I cannot see how anything related to the intercooler would cause anything to do with a fouled plug. I also don't think you were dealing with a fouled plug issue to begin with.
Please repost, and use different terms that make more sense (at least to me), even if it means spelling out completely. I say this because, I think you may be trying to refer to something different, and have chosen incorrect terminology.
I also think, just based on your initial information, that you may have a deeper rooted problem. I'll be happy to help diagnose, as will others, but please provide a little more clear picture to do so.
Thanks...

 

[1970gsx]

Check the MAF sensor.

 

[Mr. T-Type]

I can't check for a blown head gasket without tearing the heads off since the car won't run/start right now.

As for the cracked intercooler pipe, 2 Supra owners and 1 GN owner all told me the same thing when I described it. They said there is usually a loud pop, then the plugs begin to foul out.

MAF sensor looked fine. What do I need to check it? I assume a voltmeter once I start the car again.

 

[JToups386]

You do not have to get the car running to check for a blown head gasket. Why do you think you would? Nothing you have described sounds convincingly like a blown head gasket problem to begin with. Blown head gaskets do not prevent the car from running. At the same time, neither does a cracked IC pipe, (of which I've never seen or heard of on a TR). A cracked IC pipe would not react any differently than a situation of being under boost, and blowing the IC hose off at the throttle body, (another common occurance on TR's). I've blown my hoses off numerous times over the years, and the car still runs (poorly and unhappily) until you pull over to reattach it. Point being - I highly, highly, highly doubt you are dealing with a cracked IC pipe. Fouled spark plugs are usually a sign of a much more serious failure.
It sounds like a possibility of many different instances of the normal failures we deal with on these cars, but it also sounds like you could've broken some internal hard parts too.

As for the oil showing on the end of the IC outlet, that's not at all uncommon either, since over time the turbo seals begin to leak and fill the IC with oil residue, which often will puddle in the IC up-pipe.

Check/swap your MAF sensor. The most basic check is to tap on it with the car running, and if the idle changes, it's usually an indication the MAF is going/gone bad. However, it sounds like you can't perform that test, per not being able to crank the car.
Also check/swap your ignition module and or coil pack, as the symptoms you describe are relative to these items failing too.

Will the motor crank/turnover at all right now? Is it just not getting spark? Make sure you're actually getting fire to the plugs.

If you're concerned about a blown head gasket, 1.) Look for milky oil, or oil in the radiator. 2.) do a compression test or leak down test. 3.) look at the plugs and see if there is any signs of moisture/coolant on them. 4.) find someone with a cooling system pressurizer, and perform that simple test.
All four of these tests can be done without the motor running, and are very good indicators of a blown hg problem.

Hopefully you're not in the same situation as another kid on the board recently, who described basically the same things you have, and it turned out the he had broke the crank.

Keep us informed, so that we can offer further insight...

 

[Turbosix6]

Make sure all your turbo connection hoses are on and tight. This sounds like the classic symptom you are experiencing. The pop is usually the hose coming off on the boost side - sometimes it still looks connected so go over every one or replace them if you haven't already. Also reset the computer to erase any eroneous codes.