Erratic idle after injector change on 182

[Chrisj21]

Hi guys, need some pointers here please.

Yesterday I changed over number 4 injector as I kept getting the Eml light coming up showing a misfire on the pot.

Injector change went fine, removed the crash cover over the fuel rail, undone the two 10mm bolts securing the fuel rail and wiggled it out, swapped over the injector and popped it all back together, it was a bit of pain re seating the injectors agian but I'm sure the ok now.

Test drove for a couple of miles and all fine, started this morning and left it idling while I defrosted, I drove to work and around 5 miles in to the journey traffic came to a stop and I noticed the reeves hunting on idle anywhere between 1100-2000rpm, continued to work as it drove fine, got to work and the same is still happening, stopped and restarted the engine and the same thing, no fault codes or Eml light.

Any ideas what this could be? Air leak around the fuel rail? I've had a look and checked I've plugged everything back where it should be and all is good.

Thanks
Chris

 

[Chrisj21]

After some searching looks like it could be an air leak around the inlet plenum I removed?

Will have more of a look this afternoon.

 

[JamesBryan]

How come you removed the inlet to do the injectors, out of curiosity?

 

[Chrisj21]

Sorry I didn't mean the inlet, I ment the cover that's over the fuel rail.

I've read on another topic that this could be the cause of the air leak?

 

[JamesBryan]

Nah, the fuel rail guard it just that... a guard. It wouldn't be causing the issue you have.

It must be an air leak of some sort. Are the injectors 100% in properly?

Might be worth checking the O-rings on the injectors for any damage too.

 

[Chrisj21]

Thanks James, I'll take off the guard later and double check the fitting, they were a pain to get in but I thought I'd seated them correctly.

Thanks for your help :up:

 

[JamesBryan]

I little bit of oil on the o-rings before you put them in helps and also stops them getting pinched.

 

[dann2707]

Have a look at the fuel rail connector too. There are two o rings and they often split when putting back together and removing.

 

[KevF182]

Was the injector exactly the same as the on ethat came off? I've read on hear about fake magneti marelli IWP042 injectors off ebay etc. The "genuine" IWP042's will come with the clip as far as I can gather.

Second what has been said about the fuel hose connection, I've had to replace an o ring there recently as it was damaged. If you can't see leaking fuel though, its unlikely to be a problem with the fitting you've done, IMO.

It does sound like an air leak into the inlet though

 

[Brett]

@JamesBryan and I are resident injector changing experts after doing it three times in half an hour on mine last week only to find out it was a knackered HT lead causing the misfire this time.

 

[joebloggz]

Dont assume your new injector is fine.i changed all 4 last week didnt look like originals they were no good.got my money back bought the propper ones and its perfect piss easy job also.if its struggling to start its points to an air leak.

 

[ADS_V6]

hi can i ask which seller it was as about to order 4 cheers

 

[joebloggz]

Hi i wont say on here who the bad ones were off for obvious reasons .but get the ones off renparts on ebay £32.50 each im sure others on here will vouch for this. these are the exact same ones with no problems and come with clips .

 

[Chrisj21]

Thanks for all the replays guys!

Just to update this, I took off the injectors/rail again and refitted with a light smear of oil around the o rings as suggested by James. It has now solved the hunting idle problem so I can say it was most probably an air leak where I hadn't installed the injector correctly. I've done around 60miles since and all good.

Unfortunately it hasn't resolved my EML light coming on so I'm still hunting down that problem.

Also to add the injector was purchased off ebay from Renparts and is a genuine item complete with clip. I will be buying the other three and possibly a new rail too in the near future.

Cheers

 

[JamesBryan]

Good news about the air leak.

Is the EML constant or flashing?

 

[Chrisj21]

Constant James, my code reader threw up P0304 hence my changing of the injector after reading a few threads on here.

I always run BP ultimate and ran some red ex through which seemed to help for a bit, I'll try leads and plugs next although it was serviced in August. Maybe coil pack?

Once I turn it off it tends to re surface if left idling.

 

[JamesBryan]

Tesco Momentum 99 or V-Power is what most tend to use, not that the BP Ultimate would be causing the issue.

If the plugs haven't been changed, it might be worth giving them a go. Get the NGK PFR6E-10, don't bother with any other plug in my opinion.

 

[rejclarke]

I changed my injectors recently & ended up with an air leak. Turns out I'd slightly over-tightened the plastic engine cover. Removed it now & voila - no more hunting. As for the EML, I carried out the routine for turning the service light out to no avail but tgen after a long drive the next day, the EML strangely went out too. French cars eh!!

 

[KevF182]

Without getting the engine on live timing its just guessing now. But as we're on a forum I'd bet that the pre-cat lambda is not responding quickly enough.

 

[dann2707]

I changed my injectors recently & ended up with an air leak. Turns out I'd slightly over-tightened the plastic engine cover. Removed it now & voila - no more hunting. As for the EML, I carried out the routine for turning the service light out to no avail but tgen after a long drive the next day, the EML strangely went out too. French cars eh!!

Why would the engine cover cause an air leak?! Or did you mean the injector cover? So confused haha

 

[rejclarke]

I think its the bolts at the front making the inlet manifold move slightly If tthey're too tight

 

[OH182]

I've just had the DF110 code on my 182 and it was pinpointed to injector 3 so ordered one off ebay turned up and it wasn't genuine. Fitted the part and all seemed fine messaged seller about the claimed genuine injector and they refunded me £10, until running it today. Had trouble starting which I would attribute to an air leak but the management light is flashing again when left at idle. Is there a chance that the fake injector is causing the problem again?

 

[joeltalbotdj]

I have this exact same problem pal, i know how annoying it is. I checked the code and it pointed to pot 3, checked the ohms around it and it was busted. I bought a cheaper injector and replaced it without any worries... It drives and doesn't misfire until it idles when its warm then it gets rumbly. I'm thinking about changing the lot out, maybe fuel rail as well... can anybody recommend a decent upgrade?

 

[joebloggz]

I had flashing engine light changed injectors to the none genuine ones then i had problems in starting taking time to fire up but engine light stopped flashing.sent bogus ones back and got a refund then bought renpart ones that are the right ones with clips etc..Once fitted all was perfect that was over 3 weeks ago now and still no problems i can safely say i can now change all 4 injectors in less time than an episode of eastenders.