[V8] ANOTHER V8 won't start...and I am stumped!

[Coleman, David]

Good points -- fuel pressure regulator in particular.   

I also meant to opine that if you haven't heard a V8 turn but not start
in a while, or you're used to hearing that situation with a Chevy
Citation or something, I think the V8 motor makes a more pronounced
fast, compression-less crank sound than many other motors...

Just a glimmer of optimism...

-DaveC.



-----Original Message-----
From: v8-bounces at audifans.com [mailto:v8-bounces at audifans.com] On Behalf
Of dsaad at icehouse.net
Sent: Wednesday, December 15, 2004 10:42 AM
To: v8 at audifans.com
Subject: Re: [V8] ANOTHER V8 won't start...and I am stumped!

First off I would:
- Test fuel pressure for both too high or too low condition.
- Test fuel pressure regulator to make sure fuel is not comming out of
the vacuum line (indicating a bad regulator).
- Take a fuel sample (during pressure test) and look for water

Keep in mind this motor is very persnickety about its plugs. Mine had
all sorts of starting problems with Bosch +4 plugs, but does fine with
even cheapo Champions.

I would also be tempted to do a compression test because of the fast
crank.
Mine also did this and I concluded (probably erroneously) that the rings
had carboned up and a cleaning job with "GM Top Engine Cleaner" loosened
things up.
I had low compression with a cold motor but normal compression when hot
or with added oil to the cylinders during the cold test. As I recall,
the cold compression came up quite a bit after the cleaning.
I also had a sticky fuel pump relay. In my case, the motor would seem to
want to catch just as I released the key from cranking. I fiddled with
the relay contacts a little had that problem went away.

Dave

Quoting Ben Howell <bhowell at rmi.net>:

> Yep, another V8 that won't start......
>
> Here's the situation: The car is a 91' 5 speed that doesn't get driven

> a lot. Timing belt water pump and rebuilt heads went on less than 15k 
> miles ago. Plug wires, caps, rotors, plugs were done at the same time.

> About 3 weeks ago, I started it up to move it in the driveway and 
> after about 4-5 seconds of running, it just died. I tired to restart 
> it and it doesn't even try. It turns over fast, like it has no 
> compression or like the timing belt is broken. Fearing the worst, I 
> pull a the driver's side timing belt cover for inspection and the belt

> is fine. My next suspect is the reference sender. I know they go bad
all the time as I have now put two in this car.
> The one that is in there is less than 10k miles old, but I swap in a 
> known good one anyway...same result, no start, fast crank.
>
> So, feeling dejected and defeated, I walk away and leave the car. 
> Finally this weekend I get the chance to dig into it and see what I 
> can see and here is where I am at:
>
> I get only one code and it is Intake Temp Sender. I KNOW that won't 
> kill the car, but I check resistance and it is within spec AND I swap 
> in a known good one. Still no start.
>
> Now I fear a timing belt jump. I pull both caps and both valve covers 
> and bring crank up on TDC. All cams and distributors are in time. 
> Nothing has skipped anywhere.
>
> I stick a spark plug in a wire end and crank....I see a spark, so now 
> I know I have a good spark. Still no start.
>
> Now, I run the output test to see if the injectors are firing. All 8 
> injectors pass the output test (or at least the click like they are 
> supposed to). Still no start.
>
> Now I pull the plugs out. All 8 plugs range from extremely to somewhat

> fouled. So, I replace all 8 plugs with new units. Now it's almost like

> it wants to start. I can hear it trying to catch, but then it just 
> starts to crank fast again. So, I pull all the plugs back out and they

> are soaked in fuel. I blow all the gas off the plugs with compressed 
> air, pull the fuel pump relay and crank it over for a few seconds to 
> purge it. Now, I leave the car with the plugs out of it for 24 hours 
> in the hopes of really drying the cylinders out. After 24 hours, I 
> reinstall the plugs and hook all the plug wires up and try to start 
> it. Again, it tries to catch every few seconds, but still won't and
just ends up flooding again.
>
> So, here's the bottom line, I have seen a spark with my own two eyes, 
> the plugs are covered in fuel, so there must be fuel and I know 
> everything is in time....why will this thing not start? It makes no 
> sense. Does anyone have ANY idea. Anything? I like to think of myself 
> a being competent with these cars, but this one has me stumped.
>
> Any help is appreciated.
>
> Thanks!
> Ben
>
> P.S. I am still subscribed to the list, but I have not been getting 
> list mail for months now. So, if you could either reply direct or CC 
> me that would be great.
>
>
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