Car is laying over in 3rd....need some ideas...log attached

[Amelio]

ok fellas I have an issue with the car and it has me scratching my head.....

The car has been problem free for several years was at the track last season and had no issues...this problem has just surfaced with no changes to anything.

Basically the car is laying over really bad in 3rd....it lays over so bad that while I stay in WOT the car will come back down to idle.

as I stated this problem just came up from no where...I have not made any changes to the car at all.

This is what I know.....

The car has developed an exhaust leak at the cross over flange....this seems pretty common for the ATR headers...I seem to replace them every year or so....this is making my spool time insanely slow.

There is no fuel issue as far as supply...I have inspected and cleaned my filter...I also verified pressure with a different gauge during the problem...plenty of fuel

Now the car before did not want to pull at all in 1st or 2nd......prior to the log attached I pulled 5% of fuel out....this made the car like it should be in 1st and 2nd but as soon as it hits 3rd it nose dives!

You will see at roughly 33 seconds into the log the rpm starts dropping fast like I lifted but notice my TPS has not moved........

Is it possible the car is still too fat in 3rd and its drowning?

Is it also possible the exhaust leak is screwing with my fueling?

Thoughts and ideas please

 

[we4Mateo]

seems like ignition

 

[Amelio]

I thought about that....however I have never had all three coils go out at the same time....my next guess would be the ignition module....

The question is why would an ignition component decide to act up only in 3rd?

 

[we4Mateo]

I thought about that....however I have never had all three coils go out at the same time....my next guess would be the ignition module....

The question is why would an ignition component decide to act up only in 3rd?

A lot more load in 3rd.

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[earlbrown]

and heat. the amount of heat generated over time can be fairly consistent... and the amount of time it takes to accelerate a car of fixed weight over time can be pretty consistent.


and Murphy hangs out at racetracks when he isn't at my house screwing with me.

 

[josh young]

I've been having this on occasion also. It runs clean on scan tool: no knock, no codes good o2's. I've got a coil pack coming from Kirban's, hopefully it will be here tomorrow. Mine don't do it all the time, it's sporadic and only does it in third like you're describing. You can hit it down low and no problem. It runs normally even under moderate acceleration, but when it cuts out is when your WOT. I changed the plugs out Friday, got a busted finger for my efforts too. I'll let you know how the coil pack does for me. It seems like we are having similar issues though.

 

[SCOOBY DOO]

Doing it under load would lead me to believe it's an ignition issue.

 

[Amelio]

Yeah this has me scratching my head because I have never had all 3 coils go at the same time......it very well could be the coil pack...its a type 2 and has been on the car for 10-12 years.

I tend to think it possibly could be the ignition module because if it was taking a crap it would shut everything down likes its doing.....its not even breaking up it is plain shutting down!

I have replaced the ignition module years ago and from what I remember it caused the car to break up and spit and sputter.....this complete shut down is a new one to me.

 

[Amelio]

the heat is also a good point....it really had an attitude last week when it was 90 outside....it did not even want to pull in 1st.

Last Thursday night at a local car meet it really didn't act up at all in 1st or 2nd....this was at night and the air temps dropped 25 degrees........

Thanks for the ideas everyone......sometimes after picking at these things for a while you can over look some obvious issues.

Another reason I love this forum......sometimes you need a fresh pair of eyes to pin point a problem.......I will keep picking at it!

Thank s again

 

[we4Mateo]

The type II ignition isn't quite hot enough for a high boosted tr. Kidglok used one before eventually going tr6 so not my personal experience.

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[TurboBuRick]

Change the spark plugs first.

In my experience type 2 ignitions work just fine. Ive had one on my car for a couple years now with absolutely no limits. I run 25psi and hit 6500 rpm without a problem.

Rick

 

[aminga]

Are the trans switches OK because the log says it's in 3/4 switch is on from the first frame?

 

[bison]

The type II ignition isn't quite hot enough for a high boosted tr. Kidglok used one before eventually going tr6 so not my personal experience.

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Type 2 is an improvement over stock. Must use old GM coil and module. New ignition parts are junk


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[Amelio]

The Type II coil has been on there for a long time and I have never had an issue....as I mentioned I have replaced the module but that was years ago.

The plugs are new.......she is using some oil I am pretty sure my valve guides are worn....I put plugs in it 3 weeks ago.

As far as the 3/4 switch...yeah I don't know about that????? the trans has been great no issues......I was curious my self why it shows to be in 3rd the hole time

 

[Amelio]

I recorded another log that shows my MAF being pegged at 255 like normal then dips back to 77 and then back to 255.......this was all at WOT

Don't know if that was a glitch or I have a MAF problem????

 

[Amelio]

Here is another log....it was another pull just after the one I posted earlier.......if you go towards the end of the pull right around 34 seconds the MAF is acting a little silly. It drops from 255 to low 100's back to 255 then all the way down to 77 and back to 255....all this happens at WOT on the TPS but the rpm and boost has already dropped significantly due to the issue.....

Do you think this has anything to do with the issue I am having?

I don't see how the MAF could drop so low with all the air flow and on the flip side how could it possibly see 255 when the rpms were below 2500 and boost below 8psi????

 

[we4Mateo]

Here is another log....it was another pull just after the one I posted earlier.......if you go towards the end of the pull right around 34 seconds the MAF is acting a little silly. It drops from 255 to low 100's back to 255 then all the way down to 77 and back to 255....all this happens at WOT on the TPS but the rpm and boost has already dropped significantly due to the issue.....

Do you think this has anything to do with the issue I am having?

I don't see how the MAF could drop so low with all the air flow and on the flip side how could it possibly see 255 when the rpms were below 2500 and boost below 8psi????

Def a problem. Wiring or bad sensor.

 

[Ttype6]

Do you run the stock valve springs?

 

[Amelio]

Def a problem. Wiring or bad sensor.

Yeah I think there is something wrong with it also but I am not convinced its my problem since the rpm's start diving prior to the MAF showing an issue.

Plus I would think the MAF to be the issue if it dropped to 77g and stayed there while at WOT.


I think it must be the coil pack, the ignition module or the power going to the ignition module is being interrupted but only in 3rd is weird......so that leads me back to a load issue as pointed out which would mean part failure.

 

[Amelio]

Do you run the stock valve springs?

No...its a roller so it has behive springs.......

This is definitely not a slight layover like bad springs......its a hard some one flipped the power switch off type of lay over!