94 100 2.8 V6 issues

[dgraber460 at aol.com]

Thanks Tony.
The car never backfires or smokes, but keeps throwing O2 sensor codes. It also threw a temp sensor code Wednesday.
Having just had the intake and passenger head off, I can't remember seeing, nor can I now find the temp sensor.
Anyone know where it is on the V6 2.8? Probably on the back of the motor buried under the intake plenum and spaghetti of stuff!
My old copy of the family album went a way with a computer that died a few years ago. That would be invaluable to me now.
TIA

Dennis 
Denver



-----Original Message-----
From: Tony Hoffman <auditony at gmail.com>
To: dgraber460 at aol.com
Cc: quattro at audifans.com
Sent: Thu, May 20, 2010 10:01 am
Subject: Re: 94 100 2.8 V6 issues


You say it starts right up cold but has no power? While it has no
ower, does it backfire through the intake? Does it smoke at all?
What happens when the O2 sensor is umplugged? If it runs better warm
hen, part of the problem is the O2 sensor. However, it only comes
nto play once the engine reaches a certain temp (usually about 2
inutes of running). Not too sure where the coolant temp sensor is on
hat one, but that would definately be a good place to check as well.
ou can ohm it out and see if it is within specs at different
emperatures.
Tony
On Thu, May 20, 2010 at 8:35 AM,  <dgraber460 at aol.com> wrote:

 Oh great list of wisdom;
 A friends 2.8 V6 recently broke the belt and bent the valves on the passenger 
ead. the driver side head compression test was to spec so we only pulled the 
assenger side (budget constraints are in play here). We pulled the head, had a 
hop throw some valves in it and do a cursory check for other issues. We then 
ut it back on with new gaskets, belts, t-stat, and water pump. It fired right 
p after reassembly, and we used the proper cam alignment bar when putting it 
ack together.
 It will not run properly until warmed up. Idles OK, but no power till warm.
 It has been throwing two O2 sensor codes. "Regulation", "Regulation2". The 
lugs are nice and clean with no sign of richness. I'm guessing it has a temp 
ensor issue and doesn't richen up for cold running? But it starts well when 
old. Confusing.
 I'm familiar with the I5's but not the V6's. Which sensor (or system) do I 
tart with to figure this thing out? Yesterday it acted up after warm and lost 
ower for a time on the highway. Their descriptions of the issues are a little 
ifficult to interpret.
 I'll check the codes again this morning (cars not here yet this morning) but I 
eed a diagnostic step by step to get this figured out.
 Any help greatly appreciated.
 TIA

 Dennis
 Denver
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