How I Diagnosed a rough running Crossfire Corvette that was brought to me by one of my subscribers

[@Philcoopersworkshop]

Good thing you weren't one of those "I'm gonna give up on it" people. I liked how you explained what you did on that.

[@84c4corvetteguy5]

Thanks Buddy! I appreciate you watching my videos. I really need to stop by the school and see you guys!

[@vikingtrad3r]

awesome. these cars are very simple compared to the tpi. thankyou for relaying the fix. when i got my daughters car running, one injector was very lean. visibly less fuel. i tapped it with a screwdriver and its pattern changed to more or less match the other side. runs great now. thnx for all of your 84 videos. i think your channel is the penultimate 84 channel.

[@84c4corvetteguy5]

Thank you, I appreciate you watching and your kind words!

[@Beaux864]

Great video! Thanks for going through the process, you might have saved the rest of us some time and frustrations!

[@84c4corvetteguy5]

Glad I could help. Thanks for watching!

[@jonboy194]

great video, you took the time to explain everything really well, any tips on switching the #8 sparkplug

[@84c4corvetteguy5]

Thank you and thanks for watching! Ya number 8 is the hard one because of the HVAC box being right in the way. I use a very short spark plug that I can put a wrench on sometimes I get a ratchet down there and sometimes I loosen it with a wrench. This is not the exact socket I have but it's the general idea. www.amazon.com/Magnetic-Spark-Plug-Socket-Accessories/dp/B0CZMKN1RG/ref=asc_df_B0CZMKN1RG/?tag=hyprod-20&linkCode=df0&hvadid=693747049168&hvpos=&hvnetw=g&hvrand=13264754159421081327&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9009963&hvtargid=pla-2314904806526&mcid=ed04f4c48b523d608acd20727791cf5a&gad_source=1&th=1 Reply

[@ecobeastboyz1986]

Is there an email that I could reach out to you. I am in need of help on my 84

[@84c4corvetteguy5]

[e-mail]

[@danieljurgill1681]

Great video...Nice to see someone think things thru ! One question, does anyone make a setup to do an injector balance test ? I know it would be most difficult with only 12 psi fuel pressure ( as compared to 40 psi plus on port injected cars) , but I think it would have shown a major difference in flow rate side to side.

[@84c4corvetteguy5]

There are company's out there that have injector flow benches and they will clean and check the flow rate. I have never used one so I don't know much about it other than they do exist. One thing to keep in mind is that the injectors on a Crossfire engine use different injectors from side to side the factory part numbers ended with a 547 front and a 548 rear to compensate for the flow rate through the fuel rail I believe. Thanks for watching and commenting!

[@danieljurgill1681]

@@84c4corvetteguy5 Thinking about this video this morning...My 85 only has 1 O2 sensor on driver's side exhaust . If the 84 also has only 1 O2 sensor to monitor 1 bank, and each bank is controlled by 1 injector, then if the passenger side throttle body and injector has a restricted fuel flow this will make the drivers side exhaust O2 sensor to read LEAN , and this signal back to the ECM will force the ECM to increase fuel pulse width and richen BOTH injectors. This would explain why you had 4 rich plugs and 4 cleaner lean plugs. This interaction could create a problem either way. So the root cause was the low flow passenger injector , NOT the rich condition evident on passenger bank. For the future, the opposite cobdition could happen. If the passenger side injector was overfueling, the O2 on the drivers side exhaust would read rich, and the ECM would cut back fuel to BOTH injectors, and cause a lean condition on the passenger side bank. Very interesting !

[@84c4corvetteguy5]

@@danieljurgill1681 You are absolutely right! I didn't mention it in the video because I was just winging the discussion off the top of my head, but yes I had a lean condition going to the drivers side causing the O2 sensor to richen the fuel mixture but because only one side was lean it over fueled the passenger side causing the passenger side plugs to foul out. In a perfect world one O2 sensor works especially if you have a carburetor or one throttle body but if you have a problem with just one throttle body and your engine uses two it can really mess with your diagnosis due to only having one O2 sensor.