M35 Cable Throttlebody

[scotty nm35]

I hate the throttle on these barges with a passion, it never takes off the same. The ecu limits the throttle below 3000 revs and also at redline making it very hard to tune and generally taking off like a slug.

Hopefully this is the answer.

Any guesses what the ecu will do?

Is limp mode so bad?

[zei20l]

hmm maybe not, the ECU is programmed to not open more than 25% (or whatever it is) below 3000rpm, but it will only know this via the TPS signal going back to the ECU. Its entirely possible the car is programmed for the whole rev range at WOT.

i rekon chuck it on and let us know. hook up the TPS etc.

the service manual has a section right next to the electronic throttle with a cable operated throttle. so its entirely possible i rekon.......

what engine did that come from?

[scotty nm35]

Its off an EA Ford I think. Bolt pattern looks to be the same too.

If it works I may use the idle control valve that's on it, and just hook it up to the aircon clutch or something.

[QWK32]

From what i've seen of nissan ecu's, TPS signal has no influence on fuel/ign map load point lookup. i haven't seen how the "new generation" nissan ecu's do it but on all previous EFI models the map load tables are a RPM vs a MAF lookup and Injection Multiplier equation. TPS only has effect on other limiting/enhancement factors e.g. pre-accelleration enrichment, O2 and knock sensing, or as you have said, throttle limits on the DBW.

i know this is just another comparison of old vs new, but i don't see nissan changing there ecu programming that much between the years. i know this method of stock tune is used on the VQ30's from the A32 Maxima's, which i think is along the lines of the VQ's in the stagea???

so i'd think in theory, you would be ok to swap it over, you should get a more predictable WOT map access and tune, which is what your after. as long as the TPS was adapted to fit you would still get the pre-accelleration enhancements etc. the only issues i can see is if the ecu is looking for some kind of consistent feedback between the TPS and DBW unit, and if it doesn't get it, throwing up an error code or invoking limp mode. and any stock cruise control may be lost??

Edited December 27, 2009 by QWK32

[Chris Rogers]

hmm maybe not, the ECU is programmed to not open more than 25% (or whatever it is) below 3000rpm, but it will only know this via the TPS signal going back to the ECU. Its entirely possible the car is programmed for the whole rev range at WOT.

i rekon chuck it on and let us know. hook up the TPS etc.

the service manual has a section right next to the electronic throttle with a cable operated throttle. so its entirely possible i rekon.......

what engine did that come from?

you do know that the E51 El grand had a cable driven 3.5 in it don't you

[scotty nm35]

Chris, are you saying grab the El grand ecu?

The stock tps has two variable resistors that work opposite to each other. Unless I can get those to fit I would say the ecu will fault and go into limp mode.

My tuner doesn't think that is so bad. Apparently the Emanage can work pretty well taking full control away from the stock ecu. I can also fit a cheaper cruise control once I go cable too.

Edited December 29, 2009 by scotty nm35

[pipster11]

Chris, are you saying grab the El grand ecu?

The stock tps has two variable resistors that work opposite to each other. Unless I can get those to fit I would say the ecu will fault and go into limp mode.

My tuner doesn't think that is so bad. Apparently the Emanage can work pretty well taking full control away from the stock ecu. I can also fit a cheaper cruise control once I go cable too.

i would say that he means try the throttle off an elgrande, you will probably find that the plug is different but the mounting dimensions are similar like most nissan stuff (i've got a r32 tps that could fit onto my r31 if i wanted it to)

[Chris Rogers]

i would say that he means try the throttle off an elgrande, you will probably find that the plug is different but the mounting dimensions are similar like most nissan stuff (i've got a r32 tps that could fit onto my r31 if i wanted it to)

bingo. that said unless you are willing to do a full electrics swap its not worth the hassle. if you delve into the schematics for your car you will find that the ECU in it will not have any way to tell what the throttle is doing other than your right foot. that in itself tells the computer how wide to open the throttle in an ideal setting. throw slip and traction issues in and that changes again.

short version - the ECU in there wont support cable throttle.

[scotty nm35]

I figured that, I just cant live with the delay in throttle application anymore.

From what the 350z guys are saying, the ecu will fault as the dual tps signal no longer works. So I can either try and use the original tps with the new throttle body or just ditch the thing altogether and try and take full control with the Emanage as it will work with the ford tps. I understand it could be a time consuming mod but it wont cost much to try.

If all else fails the SAS remap may fix the problem but it will cost another 1500 and a drive to Sydney just to fix the throttle.

[iamhe77]

I figured that, I just cant live with the delay in throttle application anymore.

From what the 350z guys are saying, the ecu will fault as the dual tps signal no longer works. So I can either try and use the original tps with the new throttle body or just ditch the thing altogether and try and take full control with the Emanage as it will work with the ford tps. I understand it could be a time consuming mod but it wont cost much to try.

If all else fails the SAS remap may fix the problem but it will cost another 1500 and a drive to Sydney just to fix the throttle.

You could always look into the Ks Rom remap for a cheap(ish) removal of the throttle issue (and increase of the rev limit )

Looking for a spare ECU to use in the meantime? I think that maybe Bis-e-Bee has one.....

[scotty nm35]

Mmm, that's another option Cam. I assume they have fixed this problem with their remap.

Now wheres my learning Japanese language book.

Bis-e-bee, will you sell your spare ecu by any chance?

Edited December 29, 2009 by scotty nm35