Maddawg03 said:
The first thing ID do is VERIFY the CAUSE, OF THE PROBLEM FOR THAT, THRU ISOLATING AND TESTING, COMPONENTS AND SYSTEMS
A SHOP MANUAL IS ALMOST MANDATORY,
THESE LINKS should help
viewtopic.php?f=80&t=728
viewtopic.php?f=55&t=1241&p=3037&hilit=+sensor#p3037
viewtopic.php?f=50&t=609&p=5672#p5672
always drop back to the basics when youve got a problem, its amazing the number of times that simple things get overlooked , things that cause big problems like getting the ignition wired incorrectly or forgetting to connect sensors.
let me know how your progressing on checking thru the basics
do you have,
compression,
arethe valves adjusted,
correct ignition timing,
fuel delivery and fuel pressure,
do you have spark,at the plugs,
oil pressure,on the gauge
good fuel quality
any smoke from the exhaust?
and are you checking trouble codes, etc.
heres some basic info
viewtopic.php?f=55&t=1241
viewtopic.php?f=32&t=1401
Grumpy thanks again for offering your assistance. I'll summarize what my dad found in regards to your comments below. Wall of Text to follow.
Some additional information in addition to those questions. I was swapping intakes back to the stock intake manifold (Long story short there was an incompatibility between my stock fuel rails and the Edelbrock intake manifold that wasn't discovered until after we had everything back in the car). When my dad pulled the intake manifold off he verified we had oil in the valley so this combined with the fact that we had good pressure (somewhere around 60psi) seems to indicate that oil flow has been good all along.
We haven't confirmed it but when my dad pulled a couple plugs they were black and oily so we suspect fouled plugs may have contributed to the latest difficulties. The engine is definitely running rich. When my dad originally changed the O2 sensors he dropped the cat to get easier access and saw the exhaust was full of carbon build up. The rich condition could have fouled the plugs and the change in behavior may have just coincided with the O2 sensor change.
Our plan of attack now is first of all for me to delay my trip home to pick up the vehicle. My dad is going to get the plugs pulled and cleaned up. We are going to install my new chip. I have to order the correct fuel injectors as the 32# units I originally ordered showed up with 4 correct injectors and 4 that are for some other application (4 black - 4 yellow). My dad will install the new injectors and we will give a go again with the clean plugs. At that point we can check again for the electrical stuff (Injector resistance, Injector pulsing, spark at the plug, and compression if needed). I am hopeful that running the engine on the old tune was forcing the car to run rich and led to fouled plugs. Hopefully cleaning the plugs combined with the new tune will allow the engine to run and prevent the fouling of the plugs.
compression - My dad did not get around to checking compression.
arethe valves adjusted - The valves are adjusted correctly
correct ignition timing - My dad still believes timing is the problem but the distributor is installed correctly so the only timing adjustment comes from the computer (I think). We could still have a sensor sending false readings but it sounded like from our earlier discussion that shouldn't cause the car to not run at all.
fuel delivery and fuel pressure - He hasn't checked pressure yet, but there is fuel in the fuel rails and it did not appear to contain any moisture. The rich condition would seem to indicate that fuel delivery isn't an issue though.
do you have spark,at the plugs - This may be our culprit. My dad pulled 2 or 3 of the plugs before checking for spark and they are covered in a dark oily grime (fouled). I don't think he has actually checked for spark yet.
oil pressure,on the gauge - My dad told me what it read but I can't remember the exact number. I want to say around 60psi.
good fuel quality - This is suspect number 2. We didn't find any evidence of moisture but it is 4 month old fuel.
any smoke from the exhaust? No smoke but the tips are dripping black liquid. Not a lot but it is noticeable.
and are you checking trouble codes, etc. - Still not throwing any codes. You had mentioned a possible cpu failure. How would I definitively diagnose this (Is it process of elimination). As I understand it the computers in the LT1s are no longer available new.[/color]
theres more testing necessary
replacing the plugs and gapping them correctly, verify the ignition wire resistance and that your getting a good spark on all plugs, is mandatory at this point, verify the fuel purssure,
but a defective engine heat sensors,(coolant & mat) plugged cats, leaking injectors, bad O2 sensor data and a few other factors seem to be indicated at this point without further info, call me, Ill help narrow down the possabilities.
