[Steffen]

Hello,

I hope someone can guide me in the right direction.
I have '95 FB Formula 6speed with CAI and CAT's removed. No other modification.

The car runs fine except when I'm cruising in high gear (5th, 6th) and do a hard acceleration. The engine stumbles badly and no change in engine/vehicle speed.
When I slowly accelerate the engine behaves normal and does not stumble.

Doing the same maneuver in 3rd gear, engine speed increases and only light stumble.

No SVS lamp during this maneuver.

Any idea?

Steffen

 

[Steffen]

Hello,

I got an interface cable and tts Datamaster SW to troubleshoot my car.

I tested it and a did a WOT acceleration in Neutral to 5000rpm and was surprised that timing was retarded and the knock counted up. Did the same thing with a "gentle" throttle increase and everything was fine.

Could someone help me to analyze these data?

Regards
Steffen

 

[Steffen]

Hi.

I'm using fuel with ROZ 93.

Steffen

 

[Steffen]

This is a TTS Datamaster recording of an acceleration.
Gear 1-2-3 look okay
Shift to gear 5 and accelerate from low rpm -> engine stumbles badly. Timing does not advance.

Any ideas?

 

[Steffen]

Stumble problem solved - it was the Opti.

Old opti rotor bearings had to much radial clearance which made the timing disc stumble at low rpm.
Disc centered itself at higher rpm therefore engine ran fine.

With new Opti no stumble, hesitation or misses. Runs like new.

Steffen