Not one to be 100% sold on the benefits of fuel added injector cleaner I was toying with the idea of removing my injectors to have them cleaned on proper test bench. Is this a DIY project or better left to the shop? Is there a step by step out there I may be able to use?

Thanks for the help.

Youcef
90 C4

 

Anyone....

 

no step by step other than the factory manual that i am awaire of - it could be done with the engine in the car but.......it will require disassembling quite a bit of the intake system.
it's much easier with it out.
i personally would not do it unless you were conducting other more extensive operations such as a clutch change or a rebuild.
i would actually just replace them for about the same price (buy a flow matched set for 125.00/each or so) instead of clean/flow them
the fuel injector cleaner works pretty well (chevron), & the stock DME does not have the resolution to really take advanage of any thing less than 5% variation in flow
my 2 cents....

 

MY local dealer quoted me two hours for in and out, so I assume it is quite easy. Would anyone be able to forward me the workshop procedure for this.

Thanks

 

Youcef,

I removedthe intake system on mine, hten each injector in turn, I can't describe teh exact details other than it wasn't difficult and two-three hours was all it took.

Air filter, Blower motor, intake system were all I removed, I labelled up the headlight vacuum pipes and others and cleaned the injectors in a volatile carb cleaner. Make sure though the O rings are removed/replaced just to get a good seal when replacing them.

kevin.

 

Thanks Kevin, I appreciate your comments.

When you say you removed the intake system do you mean that you removed the aluminium intake runners and the resonance valve etc...

Totally agree on the O ring side, did you use OEM or just get them matched up?

Youcef

 

you should replace them with New - Stock - O rings to insure a good seal.
it's just time consuming. I removed the intake runners and such to allow for easy access.
I also did a valve adjustment and replaced all the plugs while i was there.
A factory mechanic should be able to do that in thier sleep - hence the much lower time for them.
you might be able to do it with the intake runners in - but if you need to remove them make sure to tape everything up to prevent stuff falling in there. I never tried though.
my 2 cents....

 

Youcef,

New stock O rings.
Yes the alluminium intake (or plastic year dependant) I removed the whole lot beause I had oil residues I also wanted to explore, but, it's easier to remove the injectors with everything clear, and the last thing you want to lose will ineviatably find it's way down the hole the injector left. Better safe than sorry, so I made everything easy for myself.

Kevin

 

Kevin,

I took your advice and removed whole lot and what a journey it turned out to be.

After completing this very simple job (everthing just unclips) I cannot see how the task can be done correctly without removing the whole intake system. Firstly there was quite a lot of sand and greasy muck arournd the injector so that when I removed the injector all this would have been destined for the cylinder!!

I also took the time to fully clean the intake system which also had a considerable build up around the resonance valve (which now functions very smoothly) and in the intake runners themselves. In fact it took me 3 cans of carb cleaner to get all the rubbish out!!

I found number 6 intake runner seal ring to be loose, that got fixed. I found the crank case vent pipe loose and oil all over the surrounding area. At first I thought the oil pressure sender was leaking but once I was able to remove the vent hose with 1 finger I quickly worked out where the oil was coming from. This also stopped a mild oil smell I used to experience when pulling up at traffic lights.The motor was out 2 years ago for a seal job so I imagine this one was forgotten!!

Onto the injectors - I was originally told not to bother cleaning the injectors as the fuel here is good enough to keep them clean....well sorry to say that is not quite true. I had the injectors tested and 3 of them were found to be 30% reduced capacity on a test bed!! All had varying levels but 30% was the lowest, I had the lot cleaned, new filters, new prindle caps and new Orings for 62USD, I was quoted 45USD for the only the Orings.

At the same time I was doing this job I decided to fix my stripped alternator shaft, I used the P-car.com DIY but inserted and welded a 13mm hex head into the shaft, works like a dream.

Total cost - including new fuel filter about 150USD.

What do you mean by "oil residues"?

Youcef

 

Hi Youcef, glad it went well, by oil residues I just mean the engine oil coating the surface of the crankcase cover, leaving a sort of very thin film....which I too thought had come from the pressure sender, turned out mine had been overfilled and blown back through the intakes etc......

Kevin

 

This seems like a fun/easy enough project for the diy'er.

So, the big question is was the effort worth it? i.e. Did you experience better performance/mpg as a result?

Taj.

 

Taj,

I have been waiting for the question on whether or not I noticed a difference in power or mpg. Quite honestly I couldnt say because at the same time I fitted back the injectors I repaired a broken hall sensor connection. There was a definite increase in power after the repairs but I cant tell you whether it was because of the injector clean.

I will scan the report on the injectors before and after the clean and you can see for yourself the difference in fuel output after they were serviced I can only think this would increase power to some degree.

I am very happy however to have a considerable amount of built up gunk removed from the intake system. The build up against the resonance flap at the bottom must have been close to 3mm. The flap operation was a lot lighter and smoother after the clean. The throttle body also was covered in gunk and I imagine that the airflow can have only benefitted from its removal.

Sorry to say fuel is very cheap here and I have never calculated mpg for any car I have owned here.

I would not actually use "easy" as the best way to describe this repair, you may need some considerable DIY experience before you would tackle this job. If you would happily fit your own shocks or adjust your rockers I say you could "easily" handle this one.

Youcef