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This is long.....
Last month our TGP decided to go all screwy on us, we have been trying all sorts of things to fix this problem and we've changed about everything we can think of we to no avail so I thought would see if anyone has any ideas now....
Here is a little background..
Mom drove it to work on a Friday, ran just fine and dandy, no big deal, great.....Dad drove it around Saturday afternoon, he said it was semi running like crap, especially when he got it under boost, it was running how it has been for some time but worse. So, I decided to take it out for a drive and data log it to possibly see what is up, so I drive it around for about 3 miles. We stopped, turned it off, back on, all fine, we pull up to a stop light, stop, attempt to get going, nothing, it starts puttering, chugging no acceleration will barely move, takes a whole bunch of gas/brake keeping the idle up to get it moving. Great, pull over, turn it off, check under the hood for anything unusual, see nothing, SO, we attempt to drive it home, it still running like total crap, limping barely at about 35 at full throttle! We get just about 5 minutes from home and pop, leaf breaks, look under the car, exhaust is GLOWING orange from the cat back. I watch the gauges the entire drive home, oil pressure is fine, water is normal; EGT is running at ONLY 800, where this engine runs NORMALLY 1100-1300. From my discussion with an experience engine builder his input it about the only way an engine can glow red *with a good cat* is by having fuel burning in the exhaust and not in the combustion chamber. His initial thoughts are timing, fuel, or mechanical.
For more info for those that don't know, or think it may help.
Built 3.2 with oh 25,000 miles?, all sorts of expensive happy goodies, engine was just out 3 months ago for a new converter because we thought the hold one was slipped/going bad causing it to shudder, we just figured that was the problem, well it still did that after and got worse for dad and then really went ape #### on me. All the sensors are newish, fuel injectors are about a year old, always ran quality 91 octane.
Here is what we've tried...
Fuel Pump - it was original so we changed it anyway, didn't help
Fuel Filter - Didn't help
Changed from a known GOOD source
TPS
Crank Trigger
Fuel Injectors
Fuel Pressure Regulator
Coil Pack
Ignition Module
Spark Plug Wires
Spark plugs are basically brand new, the ones we pulled weren't wet and didn't look out of the ordinary.
We changed computers and chips.
Unhooked the exhaust BEFORE the cat, same thing...
So, we've changed all the fuel system items, changed the ignition, still nothing, tomorrow we plan a compression test.
The engine will barely, if ever, start without help from "starting fluid" and will barely idle running at ~550-750 RPM, down from the set at 900-1000. It has only about 3-4Hg/In of vacuum at that rpm but with the throttle open at 1500 or so, vacuum shoots back up to its normal of about 11 or so.
If it will help at all, I have attached 2 8F Datamaster datalog files, one is of the engine running good and the 2nd is from the drive home when it went bad....I can attached CSV files if someone would like?
I'm by no means an expert with the datalog so I don't really no what to point out as bad and good. The biggest difference I noted is the purge canister is basically doing nothing when its running good and it was all over the place running bad and the O2 Counts were up and down fast running good as where running bad it took some time for it to up and down...also it was showing timing a lot lower running bad.
If anyone has any ideas by chance on what to we would appreciate it.
Edit
We pulled all the spark plugs out today and discovered that the front 3 spark plugs look fine and dandy and the back 3 plugs have soot all around them. We assume that means 3 of the cylinders aren't firing?
Last month our TGP decided to go all screwy on us, we have been trying all sorts of things to fix this problem and we've changed about everything we can think of we to no avail so I thought would see if anyone has any ideas now....
Here is a little background..
Mom drove it to work on a Friday, ran just fine and dandy, no big deal, great.....Dad drove it around Saturday afternoon, he said it was semi running like crap, especially when he got it under boost, it was running how it has been for some time but worse. So, I decided to take it out for a drive and data log it to possibly see what is up, so I drive it around for about 3 miles. We stopped, turned it off, back on, all fine, we pull up to a stop light, stop, attempt to get going, nothing, it starts puttering, chugging no acceleration will barely move, takes a whole bunch of gas/brake keeping the idle up to get it moving. Great, pull over, turn it off, check under the hood for anything unusual, see nothing, SO, we attempt to drive it home, it still running like total crap, limping barely at about 35 at full throttle! We get just about 5 minutes from home and pop, leaf breaks, look under the car, exhaust is GLOWING orange from the cat back. I watch the gauges the entire drive home, oil pressure is fine, water is normal; EGT is running at ONLY 800, where this engine runs NORMALLY 1100-1300. From my discussion with an experience engine builder his input it about the only way an engine can glow red *with a good cat* is by having fuel burning in the exhaust and not in the combustion chamber. His initial thoughts are timing, fuel, or mechanical.
For more info for those that don't know, or think it may help.
Built 3.2 with oh 25,000 miles?, all sorts of expensive happy goodies, engine was just out 3 months ago for a new converter because we thought the hold one was slipped/going bad causing it to shudder, we just figured that was the problem, well it still did that after and got worse for dad and then really went ape #### on me. All the sensors are newish, fuel injectors are about a year old, always ran quality 91 octane.
Here is what we've tried...
Fuel Pump - it was original so we changed it anyway, didn't help
Fuel Filter - Didn't help
Changed from a known GOOD source
TPS
Crank Trigger
Fuel Injectors
Fuel Pressure Regulator
Coil Pack
Ignition Module
Spark Plug Wires
Spark plugs are basically brand new, the ones we pulled weren't wet and didn't look out of the ordinary.
We changed computers and chips.
Unhooked the exhaust BEFORE the cat, same thing...
So, we've changed all the fuel system items, changed the ignition, still nothing, tomorrow we plan a compression test.
The engine will barely, if ever, start without help from "starting fluid" and will barely idle running at ~550-750 RPM, down from the set at 900-1000. It has only about 3-4Hg/In of vacuum at that rpm but with the throttle open at 1500 or so, vacuum shoots back up to its normal of about 11 or so.
If it will help at all, I have attached 2 8F Datamaster datalog files, one is of the engine running good and the 2nd is from the drive home when it went bad....I can attached CSV files if someone would like?
I'm by no means an expert with the datalog so I don't really no what to point out as bad and good. The biggest difference I noted is the purge canister is basically doing nothing when its running good and it was all over the place running bad and the O2 Counts were up and down fast running good as where running bad it took some time for it to up and down...also it was showing timing a lot lower running bad.
If anyone has any ideas by chance on what to we would appreciate it.
Edit
We pulled all the spark plugs out today and discovered that the front 3 spark plugs look fine and dandy and the back 3 plugs have soot all around them. We assume that means 3 of the cylinders aren't firing?