my friend's car wont rev over 5 grand

[e30polak]

we r almost finished with the swap...'98 obd1 s52 into '89 3251...413 red label ecu, 24# injectors, 3.5" hfm, tms chip for mods+ ews and speed sensor delete...car hasn't been able to rev past 5k on the tach since we've started it, with the tms chip or the stock chip...could it be that he has a 325 dme instead of and m3, or will that not make a difference with the tuning??? need answers asap, so please ring in if u have any insight...thanks

[BingM3]

we r almost finished with the swap...'98 obd1 s52 into '89 3251...413 red label ecu, 24# injectors, 3.5" hfm, tms chip for mods+ ews and speed sensor delete...car hasn't been able to rev past 5k on the tach since we've started it, with the tms chip or the stock chip...could it be that he has a 325 dme instead of and m3, or will that not make a difference with the tuning??? need answers asap, so please ring in if u have any insight...thanks

So you converted an s52 Obd2 to OBD1? I don't think that the DME is causing it, I do not know of any E36 BMW's that redlines at 5,000, only BMW that has a low RPM redline is a 528E at 5,750

What does it sound like it is cutting the REV at 5k?

This is a weird problem, maybe fuel pressure?

[SchnellerVert]

Knock sensor? Have you checked for codes?

[BimmerToad]

The M3 and the 325 DMEs are interchange-able, as long as they are the same label, and the harnesses off of a vanos M/S50 should be the same (sans auto).

I would suspect either the DME or HFM. Try a known working one of each and see if it resolves the problem.

Does the speed sensor delete just eliminate the speed limiter, or is the speed sensor signal also incorporated in the engine tuning?

[SchnellerVert]

The HFM can be removed from the loop to test if it will rev past 5k just twist the connector off. It is likely to stall as it has a hard time controlling the return to idle.

[mazur]

Does the MPG guage not work by any chance?

[e30_kid89]

Hmmmm. I would check these things:

-Vehicle speed sensor
-TPS
-The Ign. coils to see if the boots are cracked
-MAF/HFM
-Injectors/FPR

Since you've delete the speed sensor? Maybe it wont rev past cause the computer has no idea how fast you're going?

[e30polak]

speed sensor delete has no effect on the revs...it's not the hfm, tps, or any sensor...i guess we'll try a diff. dme...MATT WHERE R U ON THIS? I NEED SOME ADVICE FROM THE KING

[asubimmer]

its the speed sensor in the diff

[e30polak]

r u saying that that's the problem?

[asubimmer]

r u saying that that's the problem?

yes...

[e30polak]

thanks i'll try that...by the way totally unrelated, but wut size borbet's u runnin? ur car is pimp

[asubimmer]

7.5x16 et20 and 9x16 et15

and thanks :)

[e30polak]

but if i have a speed sensor delete on the chip, won't it disregard the reading coming from the sensor? and i'm saying that it wont rev past 5k whether the car is sitting in neutral or driving...so when it's sitting, how does the speed sensor have any effect?

[asubimmer]

not sure but I know that if its not plugged in or is broken than the car won't go over 5k. If its unplugged or deleted then how would the speedo register?