Lets have a look at this old 1989 Chevrolet C4 Corvette that was towed in for a no start diagnosis. When the customer explained the symptoms it sounded all to familiar to another video we did on the same engine, make and model. Be sure to check out the links below.
Chevy Corvette - No Start When Hot (The Diagnosis) : https://www.youtube.com/watch?v=Lbdjn_uP85A
Chevy Corvette - No Start When Hot (The Fix) : https://www.youtube.com/watch?v=G8M5jNy9KrA
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50 thoughts on “Chevrolet c4 corvette – no start diagnosis”
  1. Avataaar/Circle Created with python_avatars Mark Gunther says:

    How do six injectors go bad at the same time? Seems strange to me.

  2. Avataaar/Circle Created with python_avatars Antonio Claudio Michael says:

    Very bad Injector Waveform for sure flat-lining right out super easy Diag On this One Eric O good Video @SouthMainAutoRepairLLC

  3. Avataaar/Circle Created with python_avatars Michael Titus says:

    Excellent video! Thanks for the diagnostic explanation and demonstration.

  4. Avataaar/Circle Created with python_avatars Bart Daw says:

    I have the same car and it starts cold just fine but go on a drive , park for 30 mins and then no start with no solenoid noise and no cranking. You can push start it though.

  5. Avataaar/Circle Created with python_avatars Reed Jarvis says:

    Just watched the first two corvette videos . Yeah on the new injectors you could see the slit dip on the ramp side where the injector opened. Your a very talented mechanic! Explain things very well and solve the problems before throwing parts at it! Good job!

  6. Avataaar/Circle Created with python_avatars Johnny Jackson says:

    I disconnected one WIRE on the cooling fan and wired it back now the car will not start WHY????

  7. Avataaar/Circle Created with python_avatars Blade says:

    Hi Eric! We have a 99 C5 Corvette in our shop that belongs to my sister. While replacing the starter, one of the guys hooked up a gray/black wire to the positive on the starter that didn't belong and ever since that happened it won't start.
    They put a new PCM behind the right front wheel which solved nothing as well as a new key ignition. That's where they have gotten with it then asked for my help

    Its cranks but won't start, has no comm, lost fuel gauge it stays on Empty, engine temp gauge reads 270 all of the time when they were working fine.
    no spark, no power to the fuel relay during cranking probably no injector pulse either during cranking didn't check because fuel pump not running.

    With the key switched on this thing is sparking on #1 and #3 coils continuously using the alligator clip on coil and other end held close to ground.
    This is like a high RPM spark not just a tap tap tap, its like a blur spark. I assume it sparks on all 8 like this

    Relay # 52 under the hood is the ign relay and with the key on it non stop buzzes no doubt because the coils are firing non stop.
    If I power that relay it up it runs the engine fan wide open.

    I don't know to me it soulds like some grounds may be burned out and some wires fused together somewhere.

    Where would you start on this?

  8. Avataaar/Circle Created with python_avatars Robert Nowicki says:

    I got same problem…ran fine on sunday no start on monday

  9. Avataaar/Circle Created with python_avatars mark501w says:

    Thanks for the the vid, when you work on those c4’s buy the original gm electronics . Had a mas air flow cleaner code I couldn’t get rid of. Replaced the new after market tps from a previous code with a gm one from eBay. Code gone runs like a old Chevy truck again! This vid got me thinking about my tj Wrangler, on a warm day on a long pull ,I shut it down come back to it & it goes blub, blub,blub, then clears out & runs fine. The injections vapor lock from the heat of the cats below the manifolds. Just like the carbs of old.

  10. Avataaar/Circle Created with python_avatars Keith Avery says:

    Do you do any over the phone diagnosing?? Think I need some good advise

  11. Avataaar/Circle Created with python_avatars clyde moreno says:

    Let Hannah do the presentation while you record. Just a suggestion.

  12. Avataaar/Circle Created with python_avatars rosiegary says:

    hi i have a 90 c4 here in the uk and am looking to find out what cartridge i would need to fit into my snap on MT 2500 scanner

  13. Avataaar/Circle Created with python_avatars Jerry PEAL says:

    Happened to my 92 crank no start it was the knock sensor had two replaced them both .

  14. Avataaar/Circle Created with python_avatars A B says:

    I luv Corvettes 😳

  15. Avataaar/Circle Created with python_avatars MCS 33rd street. says:

    Were the on1 port location eny one no

  16. Avataaar/Circle Created with python_avatars Robert Tello says:

    this is A Kool Cat!! enjoy videos and his easy flow on explanations and approach.. keep on truckin partnr!!!

  17. Avataaar/Circle Created with python_avatars Sergio Gonzales says:

    Hi, I have a problem, I have 1992 Corvette, and change the distributor, I buy in Autozone for 1992 Corvette, Camaro, firebird applications, the car start normally, after 3 minutes the security light flashes and wehen I turn it off and try to start the security light stays on, after 3 minutes the car start again, as you did in video and remained the same, I put a bipass on the key resistence and nothing, can help me please?, thak you, greetings.

  18. Avataaar/Circle Created with python_avatars Mike Chiodetti says:

    The scope doesn't lie! Great Video!

  19. Avataaar/Circle Created with python_avatars Josh Weiser says:

    I have a 84 Corvette and it will start up then stalls out right away unless I apply the gas pedal until the check engine light comes on

  20. Avataaar/Circle Created with python_avatars Duncan Mac says:

    Thanks for the video.

  21. Avataaar/Circle Created with python_avatars Norman Gallant says:

    Good find

  22. Avataaar/Circle Created with python_avatars Dalton says:

    But you do it better.

  23. Avataaar/Circle Created with python_avatars MrBrandan83 says:

    You are really a genius. Thank you.

  24. Avataaar/Circle Created with python_avatars Kruger Design says:

    if you think its the fuel pump then stop wasting your time with your snap on junk, I watched you fiddle with that and jump wires and just laughed, dude just put a pressure gauge on the fuel rail connecter , that's what its for , takes about 60 sec to figure it out .

  25. Avataaar/Circle Created with python_avatars Misfit says:

    got a 88 Corvette it was my dad's till he passed won't start but for two seconds keep watching videos on how to bypass the vats and use resistors and nothing it's stubborn as hell. no idea if it's the fuel pump relay, security, injectors. could use some good advice. btw mine is a wimpy white automatic 88 lol

  26. Avataaar/Circle Created with python_avatars Justin Sandvig says:

    So I have a 93 40th edt* when I'm driving the dash lights will turn off and if I turn the car off while the dash lights are out it won't start? if lights are on and I kill it no problem firing back up???

  27. Avataaar/Circle Created with python_avatars Vena Sikora says:

    Super videa, jen tak dál… Made in czech republik

  28. Avataaar/Circle Created with python_avatars Sam Rugtiv says:

    good check out

  29. Avataaar/Circle Created with python_avatars Moving Up Auto Diagnostics says:

    Wow these Chevys… Btw I like your ending motto.

  30. Avataaar/Circle Created with python_avatars dimitri13 says:

    Man that's a good lookin car. Really wish I had bought a C4 instead of a C3, but when I was ready to buy I couldn't find a SINGLE one that I liked. So I ended up with an 81 4-spd t-tops.

  31. Avataaar/Circle Created with python_avatars David James says:

    did the customer have it fixed? if he did is there a follow up video??

  32. Avataaar/Circle Created with python_avatars watajob says:

    8 Bosch II's at 24 lb rating. You're golden. Call FIC, (Fuel injection connection). Great product, service, prices, warranty.

  33. Avataaar/Circle Created with python_avatars Ivan Hernandez says:

    i wish i was good at electrical problems 🙁 i wna learn how to use a scope and pico and all this fancy expensive stuff

  34. Avataaar/Circle Created with python_avatars ice44567 says:

    Mmmm, a 6 speed C4.

  35. Avataaar/Circle Created with python_avatars Tracy Hill says:

    another Crappy GM Product Lol 5 decades of engineering Junk haha

  36. Avataaar/Circle Created with python_avatars working shlub says:

    gotta love late 80s early 90s stuff..that t.b.i system they had was pretty reliable i never had issues. great video eric.

  37. Avataaar/Circle Created with python_avatars Johnny Rocket says:

    That is one BEAUTIFUL assistant you have there!!!!

  38. Avataaar/Circle Created with python_avatars RHEIDTECH says:

    holy shizit. just watched like 3 hrs of your vids. really good. full of knowledge…..and entertaining!…what the thunder! £0£

  39. Avataaar/Circle Created with python_avatars Justin Jose. says:

    Mr. Eric O. !!! Love the vidoes as a fellow mechanic and new yorker myself! But there is one video you are missing…… the tool box tour! 0_0 :O

  40. Avataaar/Circle Created with python_avatars wyattoneable says:

    Even on vacation I must have my SMA! Nice easy diagnostic Eric. Well done.

  41. Avataaar/Circle Created with python_avatars Bill Johnson says:

    Mrs O out cutting the grass in the beginning of this video? What a total women!

  42. Avataaar/Circle Created with python_avatars CARS LOVER says:

    ok

  43. Avataaar/Circle Created with python_avatars Richard Gill says:

    simple and sweet Dr. O

  44. Avataaar/Circle Created with python_avatars James Miller says:

    Pattern failure. Wait ! What !

  45. Avataaar/Circle Created with python_avatars Stanley Hill says:

    Nice!!! Classic Multecs still haunting the automotive world 🙂

  46. Avataaar/Circle Created with python_avatars Dr. Fadoodler says:

    Is there anywhere i can get a South Main Auto sweatshirt like yours???

  47. Avataaar/Circle Created with python_avatars Ozzstar's Cars says:

    what would the wave form ramp look like if those injectors were clogged which i suspect they are?

  48. Avataaar/Circle Created with python_avatars SPLEclipse says:

    Hannah strikes me as having no time for all your nonsense, Eric. :p J/k, she's a great helper and seems confident when she's at the shop!

  49. Avataaar/Circle Created with python_avatars Acrittendon Crittendon says:

    What is he asking ?