Engine Miss - Strange Problem With Injectors

[sifaan]

seems it's one problem after another these days :(

 

the car now has a bad engine miss - apparently due to injectors #2 and #3 not firing (*)

but the strange thing is that even when the injectors are swapped around with other cylinders, it is still #2 and #3 that are not firing.

The mechanic says when they removed the fuel rail from the cylinders, when cranking all 4 injectors squirt (just long enough to notice that they do) and after that only #1 and #4 continue to squirt.

 

So the suspicion is that it is electrical/control related (ECU not sending signals to injector) and hopefully an electrical specialist (familiar with 406s and EW10J4s) will take a look at it tomorrow. There are wiring issues with the car (related to fire in the fuse box long time ago and patchy repair job on the wiring there) but that should only affect the main harness; actually the engine harness was replaced a few months back so the wiring on that should be fine.

 

any advice from the good folks here?

 

 

(*) recently there was a similar problem which required the coil pack and an injector (I think it was #1) to be replaced; how they both went bust at the same time is not clear but anyway things worked fine after they were replaced. to be precise, we replaced the coil pack because the mechanic said that was the cause for the miss and then realized there was still a miss, and that was diagnosed to be a faulty injector. hopefully we didn't unnecessarily replace the coil pack.

[coastline taxis]

Where you been sifaan you havnt been on for a while good to see you back. Now down to buisness yours is a petrol model and we had one in a couple of years ago with a misfire on the injectors with the same symptoms as yours. after checking everything it turned out to be the crankshaft sensor as this tells the ecu when and which injector to fire. But due to the fact that you have wiring issues you really need to check the wiring from the crank sensor to the ecu and also ecu to injectors for breaks and continuity

[sifaan]

thanks coastline; have passed the info on to the mechanic; hope it is something simple to replace like the crankshaft sensor rather than the wiring which is a pandora's box all in itself!

[DaveHerns]

Have you got a spark and compression on cylinders 2 and 3 ? It's not a gasket blown between the two , is it?

[sifaan]

Sorry Dave, didn't see your message till now; the sparks were firing on all cylinders and subsequent developments suggest the gasket was not the culprit

 

the long delay was to get lexia setup on the mechanics laptop (these guys are all Pug mechs and they only have planet, not lexia) - after removing and cleaning some sensors (I don't know which exactly) and clearing errors on the ECU the engine is running fine.

Presumably some gunk built up over 10 years on some sensor was the culprit!

[coastline taxis]

Thanks for getting back to us sifaan its good when members post there results. would think its the cam and crank sensors theyve cleaned. For your info if you have puegeot planet software then you can plug a c5 in with it by using a puegot 406 software as there the same engines

[sifaan]

Thanks for getting back to us sifaan its good when members post there results. would think its the cam and crank sensors theyve cleaned. For your info if you have puegeot planet software then you can plug a c5 in with it by using a puegot 406 software as there the same engines

I was under the impression that the planet wouldn't talk to citroen's and lexia wouldn't talk to Pugs. By 406 software did you mean entering a 406 VIN (with the same type of engine) and that it would work for the engine diagnostics (but not other areas like suspension)?

[coastline taxis]

Yes you got it in one