Misfire When Hot

[davey205 7 1 Cars]

Have changed plugs, leads, rotor arm, dizzy cap, ECU temp sensor, TPS switch and oil it was fine when I put it away in 2012 this has developed over the last couple of months being in a damp old garage.

When 1st started its fine runs lovely but when it gets hot .... its fine till you start to rev it then it goes to 3 cylinders and sounds really rough.

Seems to pop a bit after revving so I was thinking over fueling but all I can say for sure is its definately heat related. :-s

Edited April 6, 2014 by davey205

[davey205 7 1 Cars]

Well today I managed to shock myself after pushing the leads in to make sure everything was tight..... does this point to anything in particular?

I've done a search and it seems the ignition module is a likely suspect when it runs rough when hot...... maybe I could borrow a ignition module / buy it if it turns out to be that.

Edited April 11, 2014 by davey205

[omega 82]

Well today I managed to shock myself after pushing the leads in to make sure everything was tight..... does this point to anything in particular? LOOSE CONNECTIONS!

I've done a search and it seems the ignition module is a likely suspect when it runs rough when hot...... maybe I could borrow a ignition module / buy it if it turns out to be that.

 

it could be your coil breaking down when it gets hot

[davey205 7 1 Cars]

Is that the round thing on a square bracket near the inlet manifold? ​

Right I'll have to get one.

Erm is the coil and ignition amp the same thing?

Edited April 13, 2014 by davey205

[welshpug 1,627]

no, the coil is the sparky thing either bolted on the middle of the inlet manifold or the side of the left hand strut top, ignition amplifier makes the sparky thing do its thing and is bolted to the alloy plate.

[davey205 7 1 Cars]

Is this the correct one?

http://imageshack.com/a/img822/7100/06y4.jpg

 

Its advertised as part number DUCELLIER 597042, but I've just been on service box and it lists 597043 as the part number ​ typo?

Edited April 13, 2014 by davey205

[welshpug 1,627]

it'll "work" fine, its from a carb 205, or a 1.9 Mi16, just a different bracket, might not fit properly, but should give a spark fine as the coil itself is the same.

[davey205 7 1 Cars]

Whats the general consensus on best brand? I see from searching that Intermotor are to be avoided.

Edited April 13, 2014 by davey205

[Tom Fenton 1,526]

In my experience that type of coil either works or doesn't. Misfire at a certain rev band around 4000rpm has always been ignition amp for me in the past.

In any case I would not go buying new bits by guesswork that's a way to waste lots of money double quick.

I would ask around for folk in your area who may have some spare items you can borrow to test.

[davey205 7 1 Cars]

It runs rough even at idle when its hot but fine till it warms up.

[davey205 7 1 Cars]

205 1.8 Diesel now complete with video;

http://videobam.com/ewraD

 

Checked for thermal paste on the ignition module - there wasn't any so added some premium cpu paste - no difference.

Edited April 18, 2014 by davey205

[davey205 7 1 Cars]

Its not the coil or ignition module I have also ruled out plugs, leads, dizzy cap, rotor arm, ecu temp sensor, tp switch.

What should I try next ?

[Tom Fenton 1,526]

Air flow meter

[davey205 7 1 Cars]

Thanks Tom, I definitely think its over fueling when i changed the plugs they were as black as the ace of spades and it pops when you lift off the gas if you rev it hard.

Oil pressure is good and runs sweet as a nut until hot.

 

I tried disconnecting the air flow meter today and wouldn't run at all...... presume this is normal?

 

Next I might try disconnecting the coolant temperature sensor I doubt its this as I've had it replaced within the last 5 years.

 

Will see if anyone on here has a afm I can borrow to test.

Edited April 25, 2014 by davey205

[davey205 7 1 Cars]

I spoke to my mechanic and he thinks its the ecu temp sensor ( I thought it had been changed recently but looking at the records well over 5 years ago ) is this a job for a beginner ?

[davey205 7 1 Cars]

Solved by cleaning the throttle body and all bits leading to air flow meter the whole thing was choked up with gunk ( I will always keep the mesh in the top of the filler cap there in the future! ) had a split hose too causing a massive air leak.

I suppose I will need to get another hose its the one going from the filler cap to yellow bung thing I've just put tape over it.

Can i put a tiny breather filter on the end of the filler cap and just block the yellow thing? I've just taped the tiny yellow hole atm.

 

Checked the plugs they were as black as anything, changed the plugs back to some old ngk ones I had in the garage cleaned thoroughly rotor arm and squirted a lot of the damp start spray about, also changed the dizzy cap the funny thing was I had two old ones and they all had a metal bit in all 4 corners but the one that was on the car only had 2 metal bits at the top :-s

 

Run it for well over an hour got really hot but didn't run rough at all, sorry if this is retarded but I'm not mechanically minded and its late and I'm tired, just posted this in case it helps someone.

[davey205 7 1 Cars]

I should add the afm cover was loose and possibly impeding the dial thing which according to this is very common on a lot of Peugeot engines http://www.aussiefrogs.com/forum/peugeot-forum/103011-peugeot-205-gti-mi16-runs-rough-backfires-dies-youve-tried-everthing.html

[davey205 7 1 Cars]

Well it started doing it again recently and no amount of cleaning of intake and check for air leaks solved it.... it turned out there was a bent wire / plug to no3 injector I suppose shorting out when very hot and metal expanded.

Just posting this in case it helps anyone.