ecu???

[2s4x0]

is it true if you use a automatic ecu on a manual car the rev limiter and governor dont exist or are higher than manual ecu? also does it do anything bad to your car if you swap the ecu's??

[projectRDM]

Rev limiter stays. Speed does not.

Welcome to 1989.

[ralphyboy]

In 1997 I bought my first 240, I have been hating that stupid speed limiter ever since. I read this was a possibility a week or so ago and I got right on ebay and bought the first auto ecu with a buy it now :bigok: . I have yet to put it in but I am looking forward to seeing if it works. Now I need to fix my HUD speedometer :(

[Dream240]

I had an idle problem after I did my auto-to-manual swap. The car would jump to 1500 RPMs anytime I came to a stop and when I would try to rev the car in neutral the idle would fall then jump then fall back again.

I was using the stock auto ECU......then I got a manual ECU installed it and problem went away. Wierd but I figured it was the auto ecu idle control for the "D" position. I deduced the ECU was trying to compensate for the auto tranny it thought I was running by raising idle when slowing to a stop to keep the car running as if it was always in drive gear.

Thsi is just my thinking....really it's a mystery. Anyone else ever have idle probs with using auto ECUs?

[drift freaq]

I had an idle problem after I did my auto-to-manual swap. The car would jump to 1500 RPMs anytime I came to a stop and when I would try to rev the car in neutral the idle would fall then jump then fall back again.

I was using the stock auto ECU......then I got a manual ECU installed it and problem went away. Wierd but I figured it was the auto ecu idle control for the "D" position. I deduced the ECU was trying to compensate for the auto tranny it thought I was running by raising idle when slowing to a stop to keep the car running as if it was always in drive gear.

Thsi is just my thinking....really it's a mystery. Anyone else ever have idle probs with using auto ECUs?
hmmmm it should not be that crazy. I have run quite a few auto ecu's and not had that much of an issue. When you come to a stop they bump to about 1100-1200 rpm and drop back to idle over a 20-30 second period. Its never been that big of a deal to me and can actually be tuned out for the most part.

[Dream240]

Ah so I'm not the only one! Well I'm so anal about my car that it lasted about 2 days then I bought a manual ECU. The higher idle was prolly also due to the fact that I had my idle adjusted waaaay to far out.

[ESone3]

this is good news. I'm having ECU issues and i still have my Auto one. This should be fine if i have an SR, no?

[mosca]

I have a auto to 5 sp swapped 240sx yet i am still using the auto ecu. the swap was done prior to my purchase of the car. The auto ecu and lack of tranny harness is creating all sorts of drivability issues. Maf codes, stalling, all kinds of problems. stick with your 5sp ecu. My 5sp ecu will be here in a few days and I cant wait to put that one in!

[!Zar!]

I have a auto to 5 sp swapped 240sx yet i am still using the auto ecu. the swap was done prior to my purchase of the car. The auto ecu and lack of tranny harness is creating all sorts of drivability issues. Maf codes, stalling, all kinds of problems. stick with your 5sp ecu. My 5sp ecu will be here in a few days and I cant wait to put that one in!


You have more problems than that.

I have swapped ecu's at/mt back and forth and have had no ill effects.

Better start finding out what's wrong with your car bud.

[ESone3]

yeah, just did an hour of searching. Auto or Man ECU is okay. Just a check engine light for the VSS, but no biggie.

[Dream240]

I have a auto to 5 sp swapped 240sx yet i am still using the auto ecu. the swap was done prior to my purchase of the car. The auto ecu and lack of tranny harness is creating all sorts of drivability issues. Maf codes, stalling, all kinds of problems. stick with your 5sp ecu. My 5sp ecu will be here in a few days and I cant wait to put that one in!

Is this an s14? If so you're better off manually wiring up the tranny sensors to the new ECU yourself. Unless you've already got a manual tranny harness.
There was a website where hey did a great write up on the splicing and such. I printed it like 5 years ago not sure where it's at now. Sorry. try searching for it if you're gonna go that route.

GL

[projectRDM]

I have a auto to 5 sp swapped 240sx yet i am still using the auto ecu. the swap was done prior to my purchase of the car. The auto ecu and lack of tranny harness is creating all sorts of drivability issues. Maf codes, stalling, all kinds of problems. stick with your 5sp ecu. My 5sp ecu will be here in a few days and I cant wait to put that one in!

The MAF has nothing to do with the lower harness, nor does anything that would stall the car, you've got something else wrong.

I run auto ECUs in a lot of manual cars, only thing you'll notice is slight idle hesitation when cold and a CEL for missing AT diagnostic lines. Nothing else is an issue.

[mosca]

Yeah a new MAF seemed to fix my drivability problems. Since I already ordered the 5sp lower harness and ecu I threw them in yesterday. Now i lost my speedometer. It was working before with the auto ecu, and i plugged it back in on the lower 5 sp tranny harness. Any suggestions?

[Dream240]

Okay so let me get this straight, you have a manual ECU, manual lower tranny harness, S14 speed sensor, replaced MAF....right?

Double check your connectors where the lower harness plugs into the engine bay harness. I think there's two plugs that you might have reversed. There should be 4 total...

You prolly have no back up lights either right? Throw any codes?

[projectRDM]

Yeah a new MAF seemed to fix my drivability problems. Since I already ordered the 5sp lower harness and ecu I threw them in yesterday. Now i lost my speedometer. It was working before with the auto ecu, and i plugged it back in on the lower 5 sp tranny harness. Any suggestions?

The 5spd lower harness doesn't directly plug in for all connections since the car is not prewired for reverse lights, neutral switch, or the 5th gear switch.