Not that the stock temp gauge is all that accurate, but have you noticed it higher in the zone when the car is sluggish, versus when it's running strong?

Check to make sure your fans are kicking on when the car is hot, too.

The car will pull timing and run slower to protect itself from detonation if it is getting close to overheating. Not sure how traction control would play a factor in this, though...

 

I don't know what's up with my car. Driving to work (hauling butt) I noticed a huge loss of power. When I switched the traction control back on, the car seemed to have a lot more power?

This isn't the first time this has happend. The last time my car had a huge loss of power I just parked it for a while to let it cool down. About an hour later the car seemed to run fine again.

The only thing that seems to be doing it is when the engine is hot. When I've been driving hard and the engine/clutch gets hot, I get a huge loss of power. The car gets extremely sluggish. When my car gets like this it runs noticably faster with the traction control on? Why would my car run faster with the traction control on?
Also, is anyone else experiencing a huge decrease in power after driving their car real hard? I mean a very noticable decrease in power.

I think I am seeing the same problem and I believe the problem is similar to the one HRM had with their supercharger install that mysteriously reset itself and dropped the car back to 290 hp. Never did hear of them resolving that. Many on the forum here talk about resetting the computer by taking hte negative pole loose for about 10 minutes. Even Padre talkes about his computer doing funny things when he is racing that require him to turn the car off and on. I think you may be right about the heat problem and that may be embodied in some code not touched by most tuning including Predator. I think when those parameters are reached the code tries to reset the car to factory defaults and when it does, over time, the tune is corrupted. Just my opinion.

 

I don't know what's up with my car. Driving to work (hauling butt) I noticed a huge loss of power. When I switched the traction control back on, the car seemed to have a lot more power?

This isn't the first time this has happend. The last time my car had a huge loss of power I just parked it for a while to let it cool down. About an hour later the car seemed to run fine again.

The only thing that seems to be doing it is when the engine is hot. When I've been driving hard and the engine/clutch gets hot, I get a huge loss of power. The car gets extremely sluggish. When my car gets like this it runs noticably faster with the traction control on? Why would my car run faster with the traction control on?
Also, is anyone else experiencing a huge decrease in power after driving their car real hard? I mean a very noticable decrease in power.

Is your car stock? If not, what did you change? It sounds like your computer is pulling timing, but from where... Things like knock, high IAT temps, high engine temps, O2 sensors, MAF issues contribute to pulling timing.

 

Is your car stock? If not, what did you change? It sounds like your computer is pulling timing, but from where... Things like knock, high IAT temps, high engine temps, O2 sensors, MAF issues contribute to pulling timing.

My car has a New Era Intake. Thats it. I just put the intake on the other day.
But I've had this problem before the intake install. The first time it happened the car was very new and I was practicing my launches. After doing a couple launches my car lost tons of power. All the way home the car was extremely sluggish. I almost drove straight to the dealership because I was so concerned. I went home and let the car sit for about an hour. Then I went back out for a drive and everything was back to normal?

 

Update

Today on my way home from work (87 degrees and humid) I started my car up and everything seemed fine. As soon as I got out on the main road I nailed the gas and the car hauled butt. It was back to normal. The car ran strong for the next few miles. Then I turned onto the Colonial Blvd and hit bumper to bumper traffic. For the next 5-7 miles or so It was stop and crawl driving. I was basically not moving for about 20 minutes.
Then a little closer to home I hit a stretch of clear road and opened her up. My car was so slow a V6 Camry would have possibly beaten me (no joke). Thats how slow my car was.

I'm really disappointed with this situation. I've never driven a car that is so effected by heat. It is definately being caused by the engine getting hot.

Living in South Florida this isn't going to be good. I'm really hoping a good tune will cure this problem.

 

Not that the stock temp gauge is all that accurate, but have you noticed it higher in the zone when the car is sluggish, versus when it's running strong?

Check to make sure your fans are kicking on when the car is hot, too.

The car will pull timing and run slower to protect itself from detonation if it is getting close to overheating. Not sure how traction control would play a factor in this, though...

The temp gauge reads fine. I've been watching it closely and its running right where it should be. The traction control isn't an issue either. Today (very hot engine) the car ran like a dog with the traction control on, so it isn't a factor.
As the weather warms up in other parts of the county it will be interesting to see if others have this problem.
Like I've mentioned. I live in South Florida and its pretty hot and humid. I also drive in heavy traffic to and from work. So my engine gets real hot.

 

i am experiencing the same results when my car is warm beofre startup. when the car has been off for a couple of hours, it moves very quickly. then if i turn it off and back on again, its significantly slower, feels like 400rwhp as opposed to near 500rwhp. its frustrating

 

I can vouch for the hot car thing. I dont know about camry slow, but i do feel a difference. The car is an animal when its not heat soaked. I took out the rubber baffles in the hood, and that seemed to help some.

 

the intake you have does not have a heat shield, so basically it is a warm/hot air intake. You say that the power loss happens after sitting in traffic. Your engine probably is seeing IAT's above 130 and is pulling so much timing because of it. I would get an LPE intake (currently on special also) or go back to the stock intake. Your IAT's are probably lower with the stock intake than with the new era. the LPE seals off the filter completely from the engine bay so it should help some. My IAT's (04 A4) are lower with the LPE than the stock box.

 

along with heatshielding your intake, it may be a good idea to get a lower thermostat... or even take it out if you don't expect it to get under 70 year-around... (i think you can still do that with cars these days). And yah... like mentioned above, make sure your fans are kicking in. Long discussion about heat issues among this forum's drag racers.

 

The IAT theory is a good one, but I've got a custom intake that draws from outside the engine bay, and I've raced it in 50* weather - and it still happens.

My electrical gremlins seems to have been associated with a loose fuse that killed my MAF and TPS sensors. But I haven't been back to the track after finding that loose fuse, so I don't know if that's the whole problem.

To the original poster: have you thrown any codes?

Padre

 

The IAT theory is a good one, but I've got a custom intake that draws from outside the engine bay, and I've raced it in 50* weather - and it still happens.

My electrical gremlins seems to have been associated with a loose fuse that killed my MAF and TPS sensors. But I haven't been back to the track after finding that loose fuse, so I don't know if that's the whole problem.

To the original poster: have you thrown any codes?

Padre

The only CEL I've gotton have been from the gas cap deal. (2 so far) Thats what the dealership told me caused it.

Today on my way to the Doctors office my car ran strong. Then I drove it to work a little while later and it wasn't running as good. Most likely because it had been sitting for just a short period of time and the engine was hot. Its also hot outside and I was in a lot of traffic.
As long as my car keeps moving and doesn't get too hot it runs pretty strong. But as soon as it gets heat soaked its slows down big time. Very noticable difference.

For the others
I really don't think the intake is the problem. Its much bigger than that. My car had the same issues before my intake install. With the stock intake on my car it got extremely sluggish after driving real hard (drag racing).
So there's a lot more to the problem than just an intake.

 

Same problem with my 2004 a4..I can drive it 10 miles home from work & it'll go like a bat outta hell even when its 90 degrees..But park it for 5 minutes & restart & it'll run like shit for 15 minutes or so.

 

The IAT issue has been discussed in great detail over the last year. It has been debated and been the genesis of many CAI kit discussions.

I have the Speed Inc. CAI. It is the cheapest and least fancy of any of them. Monitoring IAT’s on an 85* summer day here, yes, it’ll get hot when sitting still at a stoplight due to lack of airflow and what air is being ingested is from the hot engine compartment. But once the vehicle starts moving, the IAT’s drop to within 5* of the outside ambient temps in seconds. So it doesn’t sustain those high IAT’s when moving, at which time, they would be irrelevant in factoring a power loss. The IAT’s effect can be scaled down in the PCM to via a tuner.

To me this sounds like other issues than (or issues in addition to) the intake temps.

Your best bet is to get it on a dyno and have someone do some WOT runs while logging. I wonder if you guys are experiencing the erractic ’04 factory PCM tuning gremlins others and myself included have been privy to.

 

Stupid question but, would swapping the T-stat out cure this problem???

 

Nope.

Your intake AIR temps while being increased in part by a hot running engine and nearby radiator aren't going to cool much by running a cooler T-Stat. The difference in 190* coolant in the radiator and 170* coolant in the radiator isn't gonna change the fact that your IAT's are in excess of 100* well off the optimum 57* setting.

 

I would have the dealer look further on the code for gas cap issue, mine had that code and they found a loose clamp, took them all day to find it but they found it and my light has not back on since.

 

That would be an Evap system code and an EVAP system code isn't a power killer.

 

Nope.

Your intake AIR temps while being increased in part by a hot running engine and nearby radiator aren't going to cool much by running a cooler T-Stat. The difference in 190* coolant in the radiator and 170* coolant in the radiator isn't gonna change the fact that your IAT's are in excess of 100* well off the optimum 57* setting.

Makes perfect sense.

 

The factory guage is more an idiot light, no matter the temp it seems to set at the same spot.

To see actual engine temp, press the mode and sel buttons at the same time while you start the car. Then cycle the mode button until you see coolant temp. Your car might be overheating and tripping the limp home mode.

 

The factory guage is more an idiot light, no matter the temp it seems to set at the same spot.

To see actual engine temp, press the mode and sel buttons at the same time while you start the car. Then cycle the mode button until you see coolant temp. Your car might be overheating and tripping the limp home mode.

From what I understand the limp mode makes the car barely driveable? My car is still reasonably fast when the engine gets hot. Its just noticably slower than after start up (cool engine). My car runs like a horse on steriods when the engine is cool. With the engine gets hot, it just runs like a big heavy car with a big engine (decently fast, but nothing to brag about)

I also live in South Florida (90 degrees with high humidity) That has to account for some of the power loss.

So far every problem my car has had I've gone to the dealership and been able to duplicate it test driving a new car straight off the lot. They are getting a little sick of seeing me.
I'm hoping to do the same on my day off with another M6 05 GTO. I'm pretty confident the car (from the dealership) will run the same as mine after driving around in 90 degree heat in heavy traffic.

 

I read somewhere that some early 2005 GTO's had the wrong computer installed. I seem to remember something like the 6 speeds had the A4 computer. I'm a wrong on thinking I read this somewhere?

 

I encountered this loss of power when I was at the Ocean City muscle car cruise this past weekend. Stop and go traffic was the norm along a four mile boulevard.

I was in first gear the whole time (have to keep the revs up a bit and be able to do instant burnout when the pedestrians want to see one Anyway, I was spinning the tires at will until I turned off the boulevard onto the main street to go back to the beginning of the strip for a second go around.

The car felt sluggish as hell, and I could barely chirp the tires going WOT in first. Usually, I can start form 15 miles an hour, floor it, and spin the wheels all the way through first with no sign of slowing down.

Here's my theory. The manufacturer assumes that these cars (even though they are a high performance muscle car) are going to be driven by SCHMOES. The PCM is programmed accordingly to monitor and regulate the engine based off of,say, the previous five minutes of driving conditions.

If the computer thinks you are driving in stop and go traffic (maybe even drag racing would trick the copmuter into thinking this) timing is taken out, the FUEL injectors are retarded abit (maybe a poorman's displacement on demand) and the computer essentially puts the car into Super Tanga gas saving traffic jam mode. Once you're out of the traffic jam or the situation that has cuased the car to heat up, the computer needs a few minutes of normal driving to get back to the regular program.

Maybe it doesn't matter if your doing WOT runs or blipping the throttle to spin the tires, all the computer reads is that you are stop and go, so it does all of these things to protect the engine and drivetrain while you's in that situation.

I'm not a computer guy, but is it possible that this could be a routine that is independent of the programming that your average tuner modifies? That could explain why some people have lost their aftermarket tunes after encountering this power loss.

 

I encountered this loss of power when I was at the Ocean City muscle car cruise this past weekend. Stop and go traffic was the norm along a four mile boulevard.

I was in first gear the whole time (have to keep the revs up a bit and be able to do instant burnout when the pedestrians want to see one Anyway, I was spinning the tires at will until I turned off the boulevard onto the main street to go back to the beginning of the strip for a second go around.

The car felt sluggish as hell, and I could barely chirp the tires going WOT in first. Usually, I can start form 15 miles an hour, floor it, and spin the wheels all the way through first with no sign of slowing down.

Here's my theory. The manufacturer assumes that these cars (even though they are a high performance muscle car) are going to be driven by SCHMOES. The PCM is programmed accordingly to monitor and regulate the engine based off of,say, the previous five minutes of driving conditions.

If the computer thinks you are driving in stop and go traffic (maybe even drag racing would trick the copmuter into thinking this) timing is taken out, the FUEL injectors are retarded abit (maybe a poorman's displacement on demand) and the computer essentially puts the car into Super Tanga gas saving traffic jam mode. Once you're out of the traffic jam or the situation that has cuased the car to heat up, the computer needs a few minutes of normal driving to get back to the regular program.

Maybe it doesn't matter if your doing WOT runs or blipping the throttle to spin the tires, all the computer reads is that you are stop and go, so it does all of these things to protect the engine and drivetrain while you's in that situation.

I'm not a computer guy, but is it possible that this could be a routine that is independent of the programming that your average tuner modifies? That could explain why some people have lost their aftermarket tunes after encountering this power loss.

What you described is exacty what is going on with my car. When the engine get excessively hot from stop and go driving (especially on a hot day), power is significantly reduced.
I had the same problem with not being able to roast the tires. With a fresh engine (cool) I can roast the tire like crazy from 1000 rpms. But after stop and go traffic in the heat, I can barely break the tires loose. Huge power loss.

 

To see actual engine temp, press the mode and sel buttons at the same time while you start the car. Then cycle the mode button until you see coolant temp. Your car might be overheating and tripping the limp home mode.[/QUOTE]

Have any of you guys driven your cars with the display set like stated above,you'll be able to see your actual running temp,there is also a page that shows you if any codes have been thrown.