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Hi all, been a while since iv posted here.

In a nutshell im running a haltech e11v2 piggybacked onto the stock ecu (was to run auto) and basically something is giving noise to the ecu via the temp sensor, it can vary up to 30 degrees cycling as often as every half second or so. This causes big idle problems from shutting off to blowing smoke etc. Iv tried running both the wires separately (not both at the same time) to the ecu and the noise is still there.

Iv not been able to find anything out there with anyone having the same problem. Iv also tried a different sensor. The feed is getting 4.88V and the other is shared ground with the tps. That of which also gives me problems time to time. The noise is only there whilst engine is going and its not relative fluctuations to RPM.

Any pointers would be appreciated! cheers.

Hey mate, have no idea about your exact problem but I do similar work on large mining gear.

Does the feed stay stable when unplugged and engine running? Checking across the pins and also feed to ground, are there any fluctuations. With it unplugged does the ecu show a fault or just a random number (ie -30)

Does it fault at all temps or only cold/hot?

Thanks for the reply,

the feed is stable with ignition but not whilst engine is running. Hot and cold doesnt matter basically the same thing. Only its worse under 70 degrees because its fluctuating cold start curcuit.

I cant disconnect it as its resistance based, if I unplug it it goes to -60 or something, which instantly kills the engine. Im going to try earth the sensor to battery but not sure if that will work.

Id kick off the alternator belt next incase it's done a diode and has a slightly erratic voltage output. And double check ecu voltage for stability.

Have you done any recent welding on the car?

Id kick off the alternator belt next incase it's done a diode and has a slightly erratic voltage output. And double check ecu voltage for stability.

Have you done any recent welding on the car?

Probe the TPS to see if it is doing bullshit to the voltage on the common earth?

I have swapped the alternator to one with half the kms, and no welding for a long time before this began. It literally happened after being parked for 5 days.

I have run wires directly from ecu to sensor to no resolve. Im thinking of going straight from the ground on the sensor to the negative terminal on battery to rule out poor earth feed?

An GTSBoy, the tps is also brand new haha originally it was my only issue. Itd just lose the zero setting and try to idle out of the base map

Maybe give main chassis earths a clean too, I'd check from batt neg to sensor neg and see if it's 0v. If so I can't see it hurting earthing out the sensor to check

Yeah iv checked it all, and made a big 35 square cable for engine earth too

Does the problem change with tps disconnected? Same pulsing?

I cant unplug it or it dies lol. needs the reading to go into zero throttle idle map.

Ill have a play later in the week when I get a chance lol

  • 2 weeks later...

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