s52 acceleration problem

[Plynch2]

Hello im having a problem with acceleration, the car cuts out (lean) thru out the rpm its hard for me to explain i have a video. http://youtu.be/3Yb5HWRpcD8

spec.
obd1 s52 e34 auto harness 413 red vss is working.
I have already replaced the cam position sensor and the crank position sensor.
I have no codes.
The car has a eaton m90 on it.
But the car dose the same thing N/A
I am stuck.

[maclogos]

Did you check that the ignition coil boots are not cracked and arching? I had the same issue with my M50 and turned out all my ignition coil boots were cracked. I replaced all 6 and had no more issues.

[e-dirtym52]

My m52 obd1 has a similar issue. It will somewhat surge at half throttle but at full throttle it falls flat with a lot of backfiring when letting off of the pedal. But I'm beginning to think mines more banks or timing related. Are you sure your oxy sensor is working right? Or check your fpr?

[e30rapidic]

do you have a fuel pressure gauge?

[Plynch2]

Did you check that the ignition coil boots are not cracked and arching? I had the same issue with my M50 and turned out all my ignition coil boots were cracked. I replaced all 6 and had no more issues.

I will check but i think its fuel related because it cuts fuel, no back firing.

[Plynch2]

do you have a fuel pressure gauge?

Fuel pressure is good, after the hiccups in the higher rpm the AFR are great.

[Plynch2]

The only thing i can think of is the valve timing is off. The head was off at one point.

[e-dirtym52]

If you're a quarter to half throttle does it surge? Or have issues going uphill at a steady pace?

[Plynch2]

If you're a quarter to half throttle does it surge? Or have issues going uphill at a steady pace?

nope drives fine.

[nl328i]

If you're a quarter to half throttle does it surge? Or have issues going uphill at a steady pace?

Can you elaborate as why partial throttle or a hill can impact on hesitation/surge? Fill me in!

[e-dirtym52]

I'm still trying to figure out why that's happening with my set up! Haha. The surging or hesitation can be caused from numerous things. But my next step is replacing my oxy sensor and checking my timing. If timing seems OK then I'm replacing vanos. So if I were you I would follow those and see if you find anything Along those lines. But good luck man

[Plynch2]

Well lastnight I cleared my cel and on the way to work this morning it was back on and now I'm getting.

(1211 DME Motronic Computer Fault This may indicate a problem with the DME computer. Most problems result in a dead computer that cannot give out codes, so this particular code is not seen too commonly. If the code does appear, start and rerun the test for about one minute. If the code reappears, then chances are that you need to replace your DME computer)
So I guess ill try a different DME.

[e-dirtym52]

I have a spare 413 red label. I've already tested it out. But you could also try undoing the battery and reset everything and see if you get the same code. What tune are you running?

[NickL]

I'm assuming you're chipped for the correct modifications and injector size?

[Plynch2]

I'm assuming you're chipped for the correct modifications and injector size?

yes i have it chiped for the mods. This problem is not in the tuning.
I reset the DME let the car idle for 5 min drove it for ten the problem still recurred but no CEL. Shut the car off and then restart the CEL never shuts off pull the code and its 1211. BTW the problem isn't as bad when the car is cold, but the DME gets very hot after awhile. like i said DME is next.