Technical Missfire After Adding "cataclean"

[Mike.]

Hi, I dont know if it is coincidence or not, but on Wed. i added a can of "CATACLEAN" to my "51" PUNTO 16v and as soon as i had done a few miles a missfire started. The missfire is really bad and is troughout the entire rev. range. I have replaced the plugs with NGK and have checked that they are all fireing by running the engine with the plug connected to the lead, but sitting on top the rocker cover so as to see the spark.
I am convinced that it must be a fuel problem. Could the Cataclean have affected the injectors or caused one to fail? Looking at the plugs that came out (NGK's) no 2 looked as though it hadnt been fireing. I understand that injectors are EXPENSIVE so did not want to risk buying a set, fitting them only to find that the missfire is still there.

Any advice appreciated.

Mike.

 

[beau]

i suppose its possible that its cleaned the crap out the tank into one of the injectors and completly clogged it up...

 

[marty61]

DO NOT run the engine with a spark plug removed and sitting on top of the rocker sparking, Serious risk of fuel vapor exploding. If you need to check plug leads etc use a spare plug and leave the other ones in. Could be some dislodged c**p is blocking an injector, Coil failing, valve problem. I reckon Injector prob

 

[Mike.]

Thanks for the info, its what i was thinking i.e. injector blocked. Are they easy to take out and clean? It had a new coil pack in April.

Mike

P.S.
I did leave the plugs in and use a spare to test that the ignition was O.K. but thanks for the reminder anyway.

 

[Mike.]

Things have got a bit more frustrating. I have spent most of my day off getting more and more depressed. I have taken the fuel rail/injector system out and tested it by connecting the high pressure fuel supply hose, to pressurize the system, then put a current across each injector in turn to see if it "injected". They all gave a very even generous spray. As i have already said in my post, i have checked for a spark at each cylinder, with success. So i have each cylinder getting fuel and a spark, so why the missfire? I am at a loss as to what to do next.

Any ideas appreciated

Thanks Mike

 

[Mdeko]

i would try putting some redex in the tank and some high octane fuel to see if it cures itself. If it was caused by crap moving into the injector/another part of the engine redex may cure it.

 

[bigbadjohn]

i recently started using redex in my 04 active sport and my fuel now lasts almost twice as long and its not expensive.got a bottle in asda for bout 3quid.

 

[ChrisUK]

i recently started using redex in my 04 active sport and my fuel now lasts almost twice as long and its not expensive.got a bottle in asda for bout 3quid.

Wow works mirracles then

 

[shaun2007]

I dont know if this helps mate but I found that the upstream Lambda probe is very sensitive to various chemicals. I wreaked mine by using WD 40 around the inlet/throttle body.
Ironically it could be the cleaner thats mucked yours up?
I had no warning lights up at all on my dash incidentally. Easy enough to change and completely cured my car.

Good luck mate.

 

[Mike.]

THANKS FOR ALL THE ADVICE GUYS. have admitted defeat and taken it to my local garage. Will keep you informed. Mike.

 

[dj_jl]

:idea: Maybe after all cleaning it has done engine parameters have changed significantly and you need to reset ECU to make it relearn new parameters.