[V8] Low compression - Baffled

[32vquattro]

Start with the basics. Is it getting fuel? How about spark? How does oil
look? Get back to us with these results, and i'm sure we(us as a collective
list, that is) can figure this out.



----- Original Message ----- 
From: "Tony and Lillie" <tonyandlillie1 at earthlink.net>
To: "V8 Audi Fans" <v8 at audifans.com>
Sent: Saturday, February 17, 2007 7:18 PM
Subject: [V8] Low compression - Baffled


> Fellow V8 Audifans,
>
> I may have come to the end of the V8. I'm completely baffled, and I'm no 
> stranger to these car.
>
> I have a 1991 V8 with 325 K miles, in pretty good condition. It's an auto 
> car.
>
> It ran great up until about two months ago. It's an occasional driver, so 
> sometimes it will sit for two weeks or so. Anyhow, after sitting about two 
> weeks, it wouldn't start. I drove the 4kq and let it sit for a while. I've 
> been poking at it on and off, but now my 4k got wrecked (I'm OK, but I'm 
> still dealing with the ins), I have decided to try to get this car running 
> again.
>
> Of course, right off I noticed that the car was turning over too fast and 
> not evenly (low compression in one or more cylinders), so the first thing 
> I did was to check the valve timing. I did the TB about 15k ago, so right 
> away I assumed I screwed up the tensioner or something. Well, not the 
> case. I've checked the timing with the mark on the pulley, and the dots on 
> the chain sprockets, Dead on. Oh, and I verified the Crank mark with as 
> being TDC for # 1, as that was another thing I recently dealt with on the 
> 4k.
>
> So, I did a compression test, and here are the results :(  Keep in mind 
> that this is a cold engine not run in about 2 months. I use the five pump 
> method when and engine is cold, using a remote starter switch.
>
> #1: 120 psi
> #2: 120 psi
> #3: 40psi
> #4: 45 psi
> #5: 50psi
> #6: 15 psi
> #7: 90 psi
> #8: 60 psi
>
> The funny thing is, If they were all down I could look ofr an intake or 
> exhaust restriction. But, with them not even, I don't know what happened. 
> And, it was rather sudden, as the car ran great before. I drive it hard 
> (5000 RPM or more each shift till at speed) and would notice one or two 
> cylinders down. I would also suspect this negates the chance for carbon to 
> build up :)
>
> So, anyone out there have any ideas for me?
>
> The car does have oil in it, coolant is full. I do have spark and fuel, 
> these were the first things I checked for.
>
> Tony Hoffman
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