Intermittent random misfiring diesel

[Bizzy9]

Former Berlingo guy. Now Peugeot Partner 2014 1.6 HDI. (apologies but I'm getting no response in the Peugeot forum)

I have been getting random episodes of misfiring. One injector failed recently and was replaced. Still getting the misfiring.

Car always starts fine. Drives fine when cold. But then it will randomly begin to misfire sometimes. Yesterday it misfired for about 10 minutes. Then I stopped to go into supermarket. When I came out the misfiring had stopped.

No warning lights on dash. Mechanic can find no faults using diagnostic scan.

Searching the internet so far I have come across a couple of possible causes.

• Faulty crankshaft sensor
  
• Faulty EGR valve
  

Have any of you Berlingo diesel folk got any other suggestions or had a similar experience ?

[Multispacer]

Former Berlingo guy. Now Peugeot Partner 2014 1.6 HDI. (apologies but I'm getting no response in the Peugeot forum)

I have been getting random episodes of misfiring. One injector failed recently and was replaced. Still getting the misfiring.

Car always starts fine. Drives fine when cold. But then it will randomly begin to misfire sometimes. Yesterday it misfired for about 10 minutes. Then I stopped to go into supermarket. When I came out the misfiring had stopped.

No warning lights on dash. Mechanic can find no faults using diagnostic scan.

Searching the internet so far I have come across a couple of possible causes.

• Faulty crankshaft sensor
  
• Faulty EGR valve
  

Have any of you Berlingo diesel folk got any other suggestions or had a similar experience ?

I haven't had this experience but on checking through this forum history, there is a thread about misfiring on a 1.6Hdi and it turned out in that particular case, it was an injector problem [which was replaced] but then the problem was still occurring an it turned out to be that the replaced injector was the incorrect part number and was from a 90HP 1.6Hdi and not a 110HP 1.6Hdi. I must admit, I didn't know they were different but seeing as you have had an injector replaced, it may be worth checking that the correct p/no for your engine was fitted?

Other causes that have been mentioned include the MAF sensor.

The fact that your mechanic states there was no fault codes in the diagnostic [I assume he was using kit that detects PSA group vehicles fault codes, as generic readers do not work well on PSA vehicles?] to me would point at maybe the incorrect injector [or maybe the new one being faulty?]

Both the EGR valve and the crankshaft sensor should/would cause fault codes normally as they are both electronically controlled on the 1.6Hdi engine so it's a bit weird if it is them that no codes were seen?

Keep us updated on the forum, as it's always good to find out the solution to some of these less common faults.

[Bizzy9]

Thanks very much.

This car has been misfiring occasionally from before the injector was replaced. I had hoped that the replacement would solve the misfiring. So I'm assuming that something else is causing the problem.

I shall add MAF sensor to my list of suspects.

[Multispacer]

Thanks very much.

This car has been misfiring occasionally from before the injector was replaced. I had hoped that the replacement would solve the misfiring. So I'm assuming that something else is causing the problem.

I shall add MAF sensor to my list of suspects.

I did realise that you had the misfire before the injector replacement. The point I was trying to make, in the previous case listed, the injector was the fault but his replacement injector was not the correct part number [from a 90HP version rather than the 110HP version] so he went looking for other problems only to later find it was the incorrect replacement injector that was still causing the misfire, after he replaced it with the correct part the problem went away, hence my asking was the injector that was replaced definitely the correct part number for your engine?

[Bizzy9]

Yes. Good point. I have another mechanic. I will ask him to check.

[shtu]

At this early stage, I would be more interested in knowing that they used a scan tool that can actuallly read the codes. Lots of the multi-brand ones either miss stuff, or give misleading information.

If you can take the airbox off, you should be able to see the part numbers of all the injectors. As long as they're all the same, no worries.
The engine ecu does need to know the codes ion the injector tops, but you can only check that using a decent scan tool.

You can probably see where this is going - don't guess, get a scan and some checks done using tooling that definitely can read the iffy PSA systems.

[Bizzy9]

At this early stage, I would be more interested in knowing that they used a scan tool that can actuallly read the codes. Lots of the multi-brand ones either miss stuff, or give misleading information.

If you can take the airbox off, you should be able to see the part numbers of all the injectors. As long as they're all the same, no worries.
The engine ecu does need to know the codes ion the injector tops, but you can only check that using a decent scan tool.

You can probably see where this is going - don't guess, get a scan and some checks done using tooling that definitely can read the iffy PSA systems.

Thanks very much. The mechanic was able to enter the code for the replacement injector. Can multi-brand scanners do that?

[shtu]

Some can. Doesn't mean they can also read all the codes.

FWIW, EGR faults are common on these. You could spend £5 on a blanking plate and see what happens, even though I hate throwing parts at a problem.

[Bizzy9]

Some can. Doesn't mean they can also read all the codes.

FWIW, EGR faults are common on these. You could spend £5 on a blanking plate and see what happens, even though I hate throwing parts at a problem.

Thanks again. I will pass this on to my mechanic.

[shtu]

No.
Stop.

When a garage is involved, you are PAYING them to find the fault.

If they cannot find the fault, shop elsewhere. All that will happen is you end up with a spectacular bill, and a retort of "you told me to try X Y and Z".

If they are clueless, find someone with a clue.