A Little Help Please


mmlcobra

GT Owner
May 25, 2013
1,215
I took my 05 Heffner TT car for a drive this AM.
Car started and drove normally at low speed,
However, upon trying to merge onto the highway it just layed down in 2 and 3 gears at approx 3500 RPM.
Tryed a few times with the same result, so returned to the garage,
With no load, the car revs easily without any "breaking up".
Visual inspection does not reveal anything obvious out of place.
No CEL.
Any suggestions would be greatly appreciated.
Thanks,
Mark
 

CanadaGT

GT Owner
Sep 28, 2006
188
Edmonton Alberta
First thing to check is fuel filter. A bitch to get at but not that bad.. Located behind dry sump oil vessel.
 
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TO AWSUM

Ford GT Owner
Mark II Lifetime
Jul 4, 2007
1,506
Niceville FL
Sounds like it's going into limp mode. Did it limit your speed to about 45 mph no matter what gear? Check your battery amperage, it may be low. The same thing happened to me and it was a weak battery. Car started easily and rev'ed rapidly, but reverted to limp mode and 45 mph.
 

mmlcobra

GT Owner
May 25, 2013
1,215
Thank you both for the responses.
Not in limp mode.
Went 80 MPH under light accelleration.
Agree that fuel filter might be suspect.
Thanks for your input.
My Best,
Mark
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,176
The fuel filter would be very near the end of the list of things I'd be looking at.

Always a good practice on TT cars to pulls the plugs and see how she has been running. Check condition of plugs and gap. Remove and clean MAF sensor.
 

mmlcobra

GT Owner
May 25, 2013
1,215
The fuel filter would be very near the end of the list of things I'd be looking at.

Always a good practice on TT cars to pulls the plugs and see how she has been running. Check condition of plugs and gap. Remove and clean MAF sensor.

Thank you sir!
 

Art138

GT Owner
Mark II Lifetime
Jan 4, 2011
624
Weston,FL
I had a similar issue with the Heffner tune a few years back. If you are running the TR6IX plugs I was advised to gap them tight..believe .25sae or .64mm.
 

mmlcobra

GT Owner
May 25, 2013
1,215
I had a similar issue with the Heffner tune a few years back. If you are running the TR6IX plugs I was advised to gap them tight..believe .25sae or .64mm.

Thank you for the input!
Best,
Mark
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,832
Largo, Florida
I agree that you should look at the plugs and MAF sensor first. The fuel filter would be the least likely culprit.
 

MarkH

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
May 19, 2007
528
Katy, Texas
First thing is to pull all plugs and make sure all look good. I wouldn't keep driving it until you figure out the issue. Twin Turbo cars act and perform differently but with the age of these vehicles we have seen different parts become an issue that you wouldn't normally see on a stock car. If you need any help please let me know.

Thanks
Mark H.
 

mmlcobra

GT Owner
May 25, 2013
1,215
I agree that you should look at the plugs and MAF sensor first. The fuel filter would be the least likely culprit.

Thank you!
 

mmlcobra

GT Owner
May 25, 2013
1,215
First thing is to pull all plugs and make sure all look good. I wouldn't keep driving it until you figure out the issue. Twin Turbo cars act and perform differently but with the age of these vehicles we have seen different parts become an issue that you wouldn't normally see on a stock car. If you need any help please let me know.

Thanks
Mark H.

Thank you for your input.
Will do as suggested.
Thank you for the response!
My Best,
Mark
 

RPM217

2005 white/blue stripe
Jun 18, 2010
1,658
Rye Brook, New York
I'm willing to bet it's the plugs too. I had the same issue, car would just break up above 3500RPM no power, spoke to Rich (GT Guy), sent me some new plugs, voila, no problem. Didn't throw a code either!!!
 

mmlcobra

GT Owner
May 25, 2013
1,215
I'm willing to bet it's the plugs too. I had the same issue, car would just break up above 3500RPM no power, spoke to Rich (GT Guy), sent me some new plugs, voila, no problem. Didn't throw a code either!!!

Thank you!
Will look at that first, as many have offered the same advice.
This is the best group of people!