limp mode random revving maniac hdi

[mayotobo]

hi all. Im new to the forum and i come bearing engine issues ha. I've scoured the net looking for possible answers but due to the complexity and seemingly borderline insane french electronics i cant find any good leads to the problem.


The problem:

I was driving along and the EML came on and shortly after the car started dropping revs and randomly losing power sometimes refusing to boost. i plugged the obd reader into it and found "P0220" (throttle position sensor switch b circuit) and "P0403" (egr control circuit). a few days later it began to idle between 800rpm and 1500rpm and is now in limp mode unwilling to rev over 2500rpm. on one or two occasions the engine cut out altogether while driving.

Ive checked the EGR valve first only to find it was never connected at all. Likely disconnected by the previous owner. ive attempted clearing the faults but they don't go away. all fuses are OK and the car looks great. that last bit dosen't have anything to do with the problem but I thought id point that out anyways

the throttle is responding as usual except for when power drops.For example if the revs are at 1200rpm at idle and I rev it, it returns to 1200rpm when i let off the throttle

ive owned the car for the last 9 months and this is the first time he started gigacting...and yes it's a he, his name is barney



Thanks for any help guys

[Poodle]

Don't worry about the egr circuit, that comes up the moment you unplug the vac solenoid. For peace of mind you can buy an inlet-side blank off ebay for less than fiver delivered and fit that.

It sounds as if your problem is the TPS, try swapping it with a known good one.

Where are you based?

[mayotobo]

Don't worry about the egr circuit, that comes up the moment you unplug the vac solenoid. For peace of mind you can buy an inlet-side blank off ebay for less than fiver delivered and fit that.

It sounds as if your problem is the TPS, try swapping it with a known good one.

Where are you based?

im actually from the west of ireland. The Irish forums for all things french are utterly rubbish with lads who hear about things from their friends dad and the likes of that and everyone seems to be a qualified mechanic. So I signed up here where people seem to have a clue what they're talking about lol.

I have the blank plate ordered just waiting for delivery. I might try changing the TPS this evening if the one i can get is the same. I have a 406 HDI for breaking and hopefully it's the same? I know Peugeot like to use a lot of the same parts across a large range of cars

cheers

[Poodle]

Hahaha too far for me to help than, good to see not everyone believes the bloke in the pub and can think for themselves.

Got a feeling 406 tps is on the pedal box, where the 306 one should be lol, or maybe that's just the multiplexed ones...? Not sure in all honesty, try it and see, not going to do any harm lol.

[DeeTurbo]

My parents had a 2002 406 and that had the same TPS as mine.

The fault described is definitely a TPS fault. I've had the same symptoms as you the first time mine went.

[mayotobo]

OK so I changed the TPS with the one from the 406 HDI (exact same location and model) and although the one already on my 306 was in poor condition when I took it out, it made no improvement when i swapped them. The EGR valve was disconnected since i got the car and never brought up a fault until this happened. Could a faulty TPS cause this? I've the battery disconnected now as well just in case there's a chance it'll reset or something. It seems to be the usual remedy for random fault codes lol

[Poodle]

Disconnecting the battery won't do anything.

I seem to remember these have a shared earth with something else that can affect the signal, try tracing the earth back and cleaning it up at its base. Failing that, you could test the wiring for continuity, and if thats ok try making a new, separate earth for the tps.