VOoDOoGTX

buy a STG 5 kit from him

sebastian944

Maybe change the DME?

fast951

You need to check the TPS while driving and when then problem occurs.

I'm sure you covered the basics, but I'll mention it anyway:
- Have you pressure tested the intake system?
- Checked your BOV?

- In your earlier post, you described the problem as hesitation/backfire/loss of power. Is the backfire from the intake (engine bay) or from the exhaust?
- Also you mention 10-15% throttle when the problem occurs. Would it occur at a different throttle angle?
- To reproduce the problem you shift from first to second, then the problem occurs around 4000rpm. If you change your shift point from first to second to a higher RPM, can you still reproduce the problem?

Do you have a AFR gauge? If so, does the car go rich or lean?

Can you narrow down the problem a bit more. Is it more sensitive to: RPM, Load, Boost, Throttle position? When reproducing the problem, try to eliminate as many variables as you can. It will expedite and simplify the discovery process.

fast951

You are hired as a salesman . And to go with the Stage 5, maybe you can talk him into a 3L 16V turbo engine? I'm sure that will solve the issue he's experiencing.

SoloRacer

Vitesse also sells chips I believe.

JMJ: How long before that MC12 passed you?

marcodarq

Hey there CPR, it appears that there is not a problem with the APE product. The original idea for this post was to describe how poorly i was treated by the company, not to bash the actual product as i actually like it quite a bit.

Seb...... tried 2 different DME's already....

Mr. Vitesse,
My problem happens while driving seemingly whenever it wants to happen...any throttle angle, on boost or off boost, almost any RPM. BUT WILL NOT HAPPEN AT IDLE or if there is no load on the engine. I have tried 2 different tps's, the original one, and a spare brand new one that i had in stock as a back up, but i will check the sweep at the KLR tomorrow night. When it begins to act up, it drops power and runs rough (like it dropped 1 or 2 cylinders) and if i try th throttle through it, it will eventually backfire through the intake track. I don't have an WBo2 installed yet( i do have an Autometer, just not installed yet as i'm looking for a cat delete pipe to go with it!!) My BOV in holding vacum at the little nipple, and i did smoke test the intake looking for leaks (inject smoke from machine into closed and blockedup intake track, find smoke, found the leak,,,,,)but there werent any.
What really sucks about this is that it happens whenever it wants to and i really haen't found a consistant way to try to duplicate it, other than what i've described. Sometimes it wont happen except once or twice a day and sometimes it will happen multiple times in very short trips. It's not sensitive to engine temp, boost, fuel level in tank etc. It seems like the only requirement is that there is a load on the engine. When it happens my fuel pressure stays good, tonight i was driving down the road watching the reference and speed sensor waveforms for anything strange, but when the car acted up, the patterns stayed good. If this was any other type of car i'd say it plug wires or ignition secondary, but mine all tests good and i don't have the cash to pony up for new ones not knowing that it's going to fix the problem. I wish i had better info for you, but if anything comes to mind, i'm all ears!!!! By the way, if i ad the cabbage, i would buy the Stage5 3.0 16v Turbo engine in a heartbeat!!! but i'm pretty sure that it's out of my pricerange!!!
thanks again,
marco

CPR

Thanks, Marco...I was just wondering what the results were with that stuff, incase I have the same problem one-day.

Good Luck with resolving the issue, hopefully you'll solve it soon and get back on the road

fast951

Marco,

Were you monitoring the Speed & Ref signals by the DME/KLR area? If yes, then you can eliminate the two. I doubt they are the cause as the problem is load related.

Some of the items that will affect the LOAD: TPS, AFM, RPM

Put your scope on the TPS (KLR #22) and AFM (DME #7) - Monitor to see any irregularity.

Next:
- Check the Engine Temp signal (also at the DME). **
- Check the wiring harness (injectors)**
- Check ignition system

** not likely the cause as the problem is load related.

Other items that could be the cause: Faulty DME and/or KLR. (if you can get access to a well functioning boxes to try, it'll save you lots of time). Try a different (well functioning) KLR chip in the KLR.

As you know, it's impossible to diagnose a engine over the internet. Use the above as pointers...

PS. It might be a good idea to change to title of this thread or start a new thread of a technical nature.

MHT

A suggestion, run the engine at night, open the hood and snap the throttle a couple of times. If there is an issue with the plug wires you might be able to see them arc to ground. A few weeks ago I had a car that was doing something like yours, it turned out to be a leaking, torn hose at the top of the breather/oil separator.

Good luck, Mark T.

marcodarq

hey folks, started a new thread on this, the story continues there....thanks.
marco