Rep Power: 0

The higher compression reading in the readout, on the contrary to Andy's stab, is probably from carbon build up in the cylinder walls. That is how compression readings increase on a car.

 
Rep Power: 350

How are you going to have carbon buildup on a cylinder wall when you have 5 rings sealing and running the lengths of them? On the top of the piston, maybe, on the valves, ok, but not enough to vary that much from cylinder to cylinder. You aren't going to be flowing that much more fuel from one injector to the next, that's just not realistic. Not to mention that carbon buildup wouldn't cause an engine to overheat like this.

 
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I did not say ANYTHING about carbon causing overheating, however it will cause compression to be noted higher than usual over an OE manual's 'acceptable guidlines'.

It is possible for failure or fuel delivery problems to occur in one cylinder. This happens quite a bit. Hence why, a lot of engine management systems have individual cylinder trimming built into them. The tuner can tune each cylinder as if it is it's own engine to help prevent this. Even the E-mangle Ultimate can do this!!!

 
Rep Power: 350

Yeah, I agree, partly. Failure or lack of delivery in one cylinder. But that won't cause a carbon buildup, it'll cause lean conditions. If there is enough buildup to cake on the top of a piston, if anything, it'll prematurely wear the rings causing LOWER compression before it causes compression to rise. I know what individual cylinder trims are. You have to be able to monitor certain parameters (EGT's or AFR's on each cylinder) or read a large enough difference on the plugs while tuning to really use them to their potential, though.

 
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I referred to lack of fuel delivery as in a lean condition and failure as an erractic injector pulse, which would lead to an excessive rich condition (injector stuck open etc..)

Maybe I should have worded myself better.

 
Rep Power: 350

Gotcha. But that much fuel would/should cause misfires and you should be able to pick up on that...

 
Rep Power: 511

So I got an appointment for next week Thursday (and no, I'm not going to be doing any driving while I wait.. if I can help it.. lol) to get my cooling system checked out and a leak down test done. If it shows my HG is totally shot, then I'm gonna authorize them to replace it. The shop quoted me at about $600 to replace it (parts + labor w/ minimal milling of the head), but if something catastrophic occurs such as a cracked head/block or a retardedly warped block, then its probably gonna hurt. I'll keep you guys updated on my situation.

 
Rep Power: 511

Hmm.. well amidst my searching, I read that (i think) gearbox had a problem with a bad radiator cap causing problems. With that said, I went out and swapped out the Mugen cap my sister got me for my OEM one and now I haven't noticed any problems whatsoever.. I even started up the car and let it sit idle for a good while and the needle stayed a bit lower than it has in the last month. Now, I'm sure my Mugen cap is a genuine Mugen cap (my sister said she paid a good bit for it), but would a radiator cap cause that much of a headache? I'm still gonna go get a leakdown test done next week and the shop is gonna take a look at my cooling system to see if everything is happy, but still, would a radiator cap really cause spontaneous heating up/overheating and be that much of a problem?

 
Rep Power: 350

It could...
Only one way to find out...

 
Rep Power: 0

It can because your cooling system is a pressurized unit dictated by the volume of coolant in the system, pressure allowed by the cap and controlling of temps through the ECU and thermostat communication.

 
Rep Power: 511

So I took my car to a performance shop for a leak down test and what they concluded is that the bulk of my problems are from the radiator cap.

They did both a compression test which resulted in 175-180 across the cylinders and a compression test that showed a 5% leak past my rings . They concluded that a 5% leak is not bad considering I have about 75k miles on the engine and it's turbo'd. Also, they looked at the turbo/manifold and found out that the gasket between my manifold and turbo is.. well, ineffective, which results in exhaust leaks and what they think may be contributing to my P0172 CEL I've had for.. hella days. My sister sent me an AEM F/IC with a pnp harness and I'm gonna start looking into a new manifold/turbo assembly. Now alls I need is a physical address for myself. lol




Cliff's notes: Results concluded that the headgasket is still doing it's job, 5% slip past the rings, manifold-turbo gasket ineffective

 
Rep Power: 297

time for a swap.. haha

 
Rep Power: 511

haha.. my thoughts exactly..

that's what I told my sister anyways.. Deciding whether to do it now or wait til my engine ***** itself.

 
Rep Power: 0

The same thing happen to me with a s-10 i had. All that was needed was a flush of the raidator and everthing was just fine after that

 
Rep Power: 511

yea.. a bad radiator cap started this headache, so i'm gonna flush my cooling system to see if it makes my car happier now..

Also, my car is no longer throwing a P0172 code, but for the first time since I've been boosting, I'm throwing a P1129 (MAP higher than expected) code. I have been running w/out a missing link since I've been boosted, too. Is there a way the AEM F/IC can fix that or should I just say screw it and get the missing link anyways? I haven't installed the F/IC yet nor have I read the manual in depth yet, so iono..

 
Rep Power: 297

how much psi u boostin. cause the stock map can only read around 10-11 ish then will throw a code after that..

 
Rep Power: 511

It's not illuminating the light itself, but its causing the code to show up. I was curious if the shop reset the light or actually fixed the P0172 problem, so I plugged in my OBD2 reader and it still gave me a yellow light but with a P1129 instead of a P0172.

As for boost levels, I'm only running 2.5 psi at most.. The first shop I took the car to told me there was a problem with a turbo causing a limited boost level..

 
Rep Power: 303

Yeah it is, I dunno about a taste though. Dogs have been known to drink it due to its sweet taste with deadly results. I would say a taste wouldn't kill you, but I wouldn't recommend it either.

 
Rep Power: 511

on the drive home from work, the P1129 code was gone and the P0172 CEL was back.. disregard any previous mentioning of these codes.. lol