RPM cut off @ 5500

[your2slow]

Hey all, just wondering what would cause a total loss of power @ 5500 RPM. I've got a 96 mx-3(OBDII)runing with a kl-ze and in first gear when i hit 5500 RPM there is no more pull, the RPMs keep going up but no pull what-so-ever. 2nd, 3rd,4th and 5th seem to be fine but 1st just cuts out. Here is some info on my ride
Stock 1.8 ECU
Stock VAF
KL-ZE
ZE IM
New headers with 2.5 from the CAT
2 O2 sensors (should be 4 but new headers only had spots for 2)
??? anything else that you need let me know. Just wanna know if anyone else has this issue with thier ZE.

<small>[ August 07, 2004, 07:21 PM: Message edited by: your2slow ]</small>

[hgallegos915]

I have heard issues with people having problems while using a k8 ecu. I thinik you need to get the klze ecu. not sure bout it yet.. i havent done the swap myself.

[papa roached]

you ever think of nabing a OBD II KL-DE VAF, im running a OBD1 K8 ECU and KL-DE VAF because thats as good as you can get of a combo save for a ZE ecu or have you tried getting the KL-DE ECU too?

[Nd4SpdSe]

I'm not too sure about OBDII Mx-3, but when i was running my K8 ECU it was running extremenly rich and drinking gas

[IanL]

Here's a logical deduction - it does not have to be correct, but it could be:

The ECU does not know what gear you are in - there is no instrumentation in a MTX to tell it. All it knows is Neutral or not-Neutral. So maybe the Neutral Switch in the tranny is out of adjustment and is saying neutral when you are in first? That could cause the ECU to restrict torque.

You can test this theory by unplugging the Neutral Switch connector. Then the engine will always think you are in gear.

[your2slow]

Originally posted by IanL:
Here's a logical deduction - it does not have to be correct, but it could be:

The ECU does not know what gear you are in - there is no instrumentation in a MTX to tell it. All it knows is Neutral or not-Neutral. So maybe the Neutral Switch in the tranny is out of adjustment and is saying neutral when you are in first? That could cause the ECU to restrict torque.

You can test this theory by unplugging the Neutral Switch connector. Then the engine will always think you are in gear.

Hmmm I'm going to try that. Never even thought of this.

[Tempus]

Originally posted by IanL:
Here's a logical deduction - it does not have to be correct, but it could be:

The ECU does not know what gear you are in - there is no instrumentation in a MTX to tell it. All it knows is Neutral or not-Neutral. So maybe the Neutral Switch in the tranny is out of adjustment and is saying neutral when you are in first? That could cause the ECU to restrict torque.

You can test this theory by unplugging the Neutral Switch connector. Then the engine will always think you are in gear.

Is the neutral switch normally open, and gets closed only when the trans is in neutral? if so your test should work fine. A better alternative might be if you have a multi-meter and a few clip leads. You should be able to disconnect the switch, connect the meter to it, and observe if the switch is open or closed in all possible positions of the trans.. (all 6 gears, and all 3 neutral positions (left, center, right)) to see if everything is behaving as it should. That test can be done sitting still

[IanL]

Originally posted by Tempus:
Is the neutral switch normally open, and gets closed only when the trans is in neutral? if so your test should work fine. A better alternative might be if you have a multi-meter and a few clip leads. You should be able to disconnect the switch, connect the meter to it, and observe if the switch is open or closed in all possible positions of the trans.. (all 6 gears, and all 3 neutral positions (left, center, right)) to see if everything is behaving as it should. That test can be done sitting still

Yes, it is only closed when in neutral, and that's an excellent idea, if it shows the problem up. But it did occur to me that it may only show when the box is transmitting torque (if the condition is marginal) so, if the test shows no problem, it would not be conclusive.

[Gro Harlem]

get an AFPR...its the one thing I still need to realize the full potential of my ZE too...i can't squeeze any power past 6500.

[IanL]

Are you suggesting that the lack of power above 5,500 rpm, but only in first gear, is caused by fuel starvation? I'm not saying you're wrong, but why only in first?

<small>[ August 09, 2004, 08:17 AM: Message edited by: IanL ]</small>

[MrMX3]

where abouts is the neutral switch on the tranny, mine started doing the same thing and was working fine for a while....

[IanL]

It seems from the manual to be below and slightly in front of the right side driveshaft, with a cable which leads rearwards and upwards.