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Limp Mode

Barras

By Barras,
in Four Door Family & Wagoneers

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Barras Explorer

Barras

Posted
Posted

G'day guys, i've been looking here for a while and finally decided to post a question.

I don't know much myself about these cars but i'm trying to learn, anyway here is my question, i have a M35, when i floor it off the mark or when driving along and put the foot through the firewall the car goes onto limp mode, i then need to turn the car off remove the key start the car up again and continue on my way, i'm putting the car in for a service in the next couple of weeks and would like to be able to tell the mechanic what might need to be replaced to fix this.

Any advice would be appreaciated.

i was trying to wait until the next Vic cruise or even the SAU nationals when i could discuss these cars with others but need to get this resolved ASAP.

Thanks

Chris

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scotty nm35 Grand Master

scotty nm35

Posted
Posted

would like to be able to tell the mechanic what might need to be replaced to fix this.

If you need to tell him how to fix it, he isn't the man for the job. Have you worked out the codes yet?

What mods do you have if any?

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Barras Explorer

Barras

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Posted

Thanks guys i'll get him to check out the AFM, he was going to put it on the dyno to check what's going on but time didn't prevail.

Iamhe77, from Forest Hill

Have even looked at codes or anything like that, the missues just drives it to and from work and thats about it.

Car is standard as far as i know except for dual DVD players in the headrests (just got the cable to run the DVD's through the front screen yesterday), Brembo brakes, Volk TE73's 245x40x19 tyres, and some sort of body kit on it, leather interior.

(still working out how to reply to multiple messages) :D

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  • 2 months later...
Commsman Veteran

Commsman

Posted
Posted

OK the problem is the throttle position sensor, now i've just got to source one to test.

Would throttle re-learn procedure fix this? Even though it is used for idle speed, it may well fix it. The guys who have done this when cleaning out their throttle bodies may know...... In any case, it shouldn't take long to do the procedure. Info here: http://www.m35stagea.info/forum/viewtopic.php?f=6&t=206

Cheers, Leon.

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zei20l Grand Master

zei20l

Posted
Posted

remember there is a throttle position sensor on the pedal and one on the actual throttle itself - actually i think there are 2 on the throttle.

if its only when you floor it, its possibly the one attached to the pedal

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Commsman Veteran

Commsman

Posted
Posted

If you want to easily check what Iain suggested, get a multimeter, earth one probe and check the voltages on the wires with the other. The voltage on pins 2 & 5 should be linear all the way to the floor. A sudden change (drop off?) would indicate a faulty potentiometer.

To get access you might need a pin to push thru the wires as the back of the connector is sealed.

post-76144-0-04601500-1317618428_thumb.jpg

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scotty nm35 Grand Master

scotty nm35

Posted
Posted

Its probably a dirty carbon track on the pot, there are two carbon tracks inside it. If you can pull it all apart and clean the tracks with contact cleaner it should be fine. Or just replace the throttle pedal sensor.

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