hmm...code 44?
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
They are bosch III 30lb injectors from Jon. And yes, the computer is tuned for this mod, along with all the other mods done to the car (see profile). It didn't run like this 6 months ago, meaning the cold running issue. The wierd cel lighting up and mpg issue is brand new. This car has been combed over with a fine tooth comb...everywhere. I just can't think of anywhere else to look besides the computer, or the tps (which checks out).
I was just hoping the symptoms would give somebody a lightbulb over the head type moment, but I guess not.
I was just hoping the symptoms would give somebody a lightbulb over the head type moment, but I guess not.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
bumpity bump bump bump!
still happening! same symptoms as before:
-rough idle/stalling when cold, occasionally dies when warm.
-Instant mpg goes way down randomly but everything else in normal, then, CEL lights up and engine pics up ~150 rpms on its own and gas mileage gets better, not normal though. After a few cycles or so...car returns to normal, mpg is normal, CEL off, car still running good. If I stop after the car has one of these "episodes", the idle is very smooth and the car is running flawlessly.
-Only code is a 44....lean exhaust present.
Please, someone shed some light!
still happening! same symptoms as before:
-rough idle/stalling when cold, occasionally dies when warm.
-Instant mpg goes way down randomly but everything else in normal, then, CEL lights up and engine pics up ~150 rpms on its own and gas mileage gets better, not normal though. After a few cycles or so...car returns to normal, mpg is normal, CEL off, car still running good. If I stop after the car has one of these "episodes", the idle is very smooth and the car is running flawlessly.
-Only code is a 44....lean exhaust present.
Please, someone shed some light!
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Sounds like alot of new parts, but I wouldn't rule out anything (sensors) just because there new. You can ohm, or check voltage on alot of them, I know alot of guys who had to replace new 02s......and once again I'd check that CTS. Hope that doesn't irritate you, but it sounds so much like a friends problem at one time.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
I am starting to think the O2 is going in and out. I was hoping the new symptoms I was experiencing could have been related to the cold running issue, but it doesn't look like thats the case. I need to check the IAC, the car idled fine before I changed it, when it actually fired under its own power.
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Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Certainly doesn't hurt to check the work you've done, IACs can be funny, (improper install, vac. leaks, different pintles etc.) but it doesn't come into play except at idle, so I'd be surprised if that were your problem, since you experienced this while cruising. Thing with the 02 and CTS is they can cause intermittents, (just like other sensors or relays) but either of these will cause a change in fuel (lean or rich). The computer can actually correct sometimes even before a code is thrown. I know that for a fact on the CTS.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
The CEL lighting up and the surging while crusing and gas mileage drop is an intermittent, happens about once every 100 miles.
The rough idle/stalling when cold is a given, happens everyday. Problem gets better as coolant temps rise. When at normal operating temps, car is running smooth, normally....a little glitch at idle here and there, nothing major.
I ohmed out the new CTS, it checks out. the connector is good. I traced all the wiring and found no breaks. O2 is new, everything looks good there.
Here's a rundown of parts replaced or known good for you guys: its long:
Fuel Pump, Fuel Injectors, IAC, TPS, O2, EST module, Timing, MAF sensor, MAF burnoff module, Fuel pressure at rail at all times, CTS, air filter, etc.
Engine (intake, heads, cam, block) all are just 2 1/2 years old. Chip tune by TPIS is dead on. Idle problem started 6 months ago, new problem started 3 weeks ago.
Oh, the car is running very rich btw. Black smoke from the pipes when I rev it up, and smells like a gas station out back. I'm really starting to think something isn't right with the spark system, just don't know what it could be.
The rough idle/stalling when cold is a given, happens everyday. Problem gets better as coolant temps rise. When at normal operating temps, car is running smooth, normally....a little glitch at idle here and there, nothing major.
I ohmed out the new CTS, it checks out. the connector is good. I traced all the wiring and found no breaks. O2 is new, everything looks good there.
Here's a rundown of parts replaced or known good for you guys: its long:
Fuel Pump, Fuel Injectors, IAC, TPS, O2, EST module, Timing, MAF sensor, MAF burnoff module, Fuel pressure at rail at all times, CTS, air filter, etc.
Engine (intake, heads, cam, block) all are just 2 1/2 years old. Chip tune by TPIS is dead on. Idle problem started 6 months ago, new problem started 3 weeks ago.
Oh, the car is running very rich btw. Black smoke from the pipes when I rev it up, and smells like a gas station out back. I'm really starting to think something isn't right with the spark system, just don't know what it could be.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
Should also mention, there is only one way the car will run and not die when cold, and that is to unplug the est (timing wire). I don't know why, but that makes the idle at around 600-700 rpms in park instead of the normal 800-900, but it doesn't surge, buck, or stall with the wire unplugged.
WHY!?
WHY!?
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
You may be right...or the computer could be whack too. I'm unclear on the limp mode thing, but unplugging the est does keep the computer from advancing or retarding timing.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Limp home mode is when something is bad and it goes into a set program and will not be able to alter the fuel trim.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
Right, i know that, just not sure if unplugging the est will put the computer in "limp mode" or not. If so, then I'm going to lean harder toward the ecm being bad. If not, I'm thinking something in the ignition, like the ICM.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Year or two ago I posted asking what were your symptoms when your ECM went bad? most guys posted "it started running pig rich". Not saying that is your problem, just wanted to throw it out. Anyone close with an ECM (same year) you can try ? And you could try cleaning the connections on it.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
Thanks Rick, the connections at the ecm are good. I combed over all the wiring in the car and didn't find anything, it actually appears to be a newer wiring harness.
However, the ecm is a reman unit from napa, and appears to be at least 8 years old.
Also, if a car is running pig rich, will retarding the timing help? If so, that could be why unplugging the est makes the car run better.
However, the ecm is a reman unit from napa, and appears to be at least 8 years old.
Also, if a car is running pig rich, will retarding the timing help? If so, that could be why unplugging the est makes the car run better.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Well, your post said a code 44, OK, following the trouble tree in the FSM, first, it would have to be scanned, but, since I don't know if you have a scanner, the last thing is check for ckt (circuit) 412 to see if it's shorted to ground or a faulty ECM.. I would like to point out that on most trouble trees the ECM is usually the last item to consider as a fault.
As far as the EST goes, I'm not quite sure as far as your question goes, but I think it would be the opposite. And here's another thing, the last item mentioned once again in the TS tree is a faulty ECM if a code 42 is set.
Do you have a scanner?
As far as the EST goes, I'm not quite sure as far as your question goes, but I think it would be the opposite. And here's another thing, the last item mentioned once again in the TS tree is a faulty ECM if a code 42 is set.
Do you have a scanner?
