C4 Down!!!
Thread Starter
Advanced
Joined: Jan 2019
Posts: 81
Likes: 15
From: New Braunfels, TX
2020 Corvette of the Year Finalist (stock)
C4 of Year Winner (stock) 2019
C4 Down!!!
Ok. I'm not asking for advice since I'm letting a shop do this one. But I will take guesses of what is may be. I don't know yet. So here's what happened.
Driving home, nothing out of the ordinary, when all of a sudden the car started to shutter and shake. It was loosing power and idling very rough. I pulled over and let it sit running and the RPMs were up and down about 5 seconds per cycle. If I tried to put it in gear it would almost die. I would turn it off and wait for about 5 mins then start again, and it would be worse. Finally, on the last time I turned it on, there was a loud scraping/tapping sound coming from engine on the front drivers side from what I heard. I was thinking timing chain, bad cylinder or something worse. I had it towed back to the house today and tried to start it and it would crank, turn over and run for about 5 seconds, very rough, but then die.
Any ideas. Like I said, I am not working on this one. Just no time. But I was wondering if anyone has experienced this before and could provide some insight.
Thank you,
Tim
Driving home, nothing out of the ordinary, when all of a sudden the car started to shutter and shake. It was loosing power and idling very rough. I pulled over and let it sit running and the RPMs were up and down about 5 seconds per cycle. If I tried to put it in gear it would almost die. I would turn it off and wait for about 5 mins then start again, and it would be worse. Finally, on the last time I turned it on, there was a loud scraping/tapping sound coming from engine on the front drivers side from what I heard. I was thinking timing chain, bad cylinder or something worse. I had it towed back to the house today and tried to start it and it would crank, turn over and run for about 5 seconds, very rough, but then die.
Any ideas. Like I said, I am not working on this one. Just no time. But I was wondering if anyone has experienced this before and could provide some insight.
Thank you,
Tim
Thread Starter
Advanced
Joined: Jan 2019
Posts: 81
Likes: 15
From: New Braunfels, TX
2020 Corvette of the Year Finalist (stock)
C4 of Year Winner (stock) 2019
Ok. I'm not asking for advice since I'm letting a shop do this one. But I will take guesses of what is may be. I don't know yet. So here's what happened.
Driving home, nothing out of the ordinary, when all of a sudden the car started to shutter and shake. It was loosing power and idling very rough. I pulled over and let it sit running and the RPMs were up and down about 5 seconds per cycle. If I tried to put it in gear it would almost die. I would turn it off and wait for about 5 mins then start again, and it would be worse. Finally, on the last time I turned it on, there was a loud scraping/tapping sound coming from engine on the front drivers side from what I heard. I was thinking timing chain, bad cylinder or something worse. I had it towed back to the house today and tried to start it and it would crank, turn over and run for about 5 seconds, very rough, but then die.
Any ideas. Like I said, I am not working on this one. Just no time. But I was wondering if anyone has experienced this before and could provide some insight.
Thank you,
Tim
Driving home, nothing out of the ordinary, when all of a sudden the car started to shutter and shake. It was loosing power and idling very rough. I pulled over and let it sit running and the RPMs were up and down about 5 seconds per cycle. If I tried to put it in gear it would almost die. I would turn it off and wait for about 5 mins then start again, and it would be worse. Finally, on the last time I turned it on, there was a loud scraping/tapping sound coming from engine on the front drivers side from what I heard. I was thinking timing chain, bad cylinder or something worse. I had it towed back to the house today and tried to start it and it would crank, turn over and run for about 5 seconds, very rough, but then die.
Any ideas. Like I said, I am not working on this one. Just no time. But I was wondering if anyone has experienced this before and could provide some insight.
Thank you,
Tim
Go figure!
Safety Car
Joined: Jul 2003
Posts: 3,500
Likes: 879
From: Saratoga Springs NY
2024 C4 of the Year Finalist - Modified
2022 C4 of the Year Finalist - Modified
Sound like trash made its way to the injectors for it to happen at once....Id look at the tank and lines to be sure theres not another underling issue. Injectors dont just clog like that. Takes time..
Thread Starter
Advanced
Joined: Jan 2019
Posts: 81
Likes: 15
From: New Braunfels, TX
2020 Corvette of the Year Finalist (stock)
C4 of Year Winner (stock) 2019
That is the nest step... What I'm puzzled at is that I just replaced the fuel filter about 3 weeks ago.
Safety Car
Joined: Jul 2003
Posts: 3,500
Likes: 879
From: Saratoga Springs NY
2024 C4 of the Year Finalist - Modified
2022 C4 of the Year Finalist - Modified
I know the vette dosent have much (or any?) rubber lines but still....Will also cause metal lines to rust, and same issue.
People tell me all the time they run super - non ethanol, but in reality you dont know what your buying unless you test it..Kits available everywhere, but its basically a glass tube you put in X amount of fuel and water. Shake it and itll tell you how much is present....Youll be suprised (and prob pissed) at the fuel your buying...
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
This brings up a question with 5 clogged injectors - what happened to the fuel filter? If it happened tank side, the filter should have caught it. If not then either the filter is crapped out or it happened post filter. If it's post filter, I'd expect unless the cause was found and fixed it could happen again.
Just some thoughts.
Just some thoughts.
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Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
This brings up a question with 5 clogged injectors - what happened to the fuel filter? If it happened tank side, the filter should have caught it. If not then either the filter is crapped out or it happened post filter. If it's post filter, I'd expect unless the cause was found and fixed it could happen again.
Just some thoughts.
Just some thoughts.
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
If he has Multecs, I'd be very careful. If not, he can afford to waste his money on placebo cures for all I care. IIRC, there was a TSB about the snake oils eating the injectors.
Oil Producer
Joined: Apr 2014
Posts: 9,371
Likes: 2,736
my bs’ometer is tingling.
how did they test your injectors? to discover they are plugged?
only way i know is to remove them and put them on a test machine.
Burning Brakes
Joined: Aug 2018
Posts: 891
Likes: 175
From: PA
They do make a tool that you use by touching the injector and it measures the solenoid clicking on and off. If it is not pulsing correctly or intermittently you can also see that. It has a beeping alarm along with a flashing light. I've seen some techs pull the fuel rail and add power to each injector just long enough to see it spray. Have to be well ventilated and be careful of spark. Marc Haibeck has a page devoted to testing by measuring the OHM's of each injector without pulling the plenum on the LT5. Not hard at all to test the resistance on the L98, LT1, LT4 .
Oil Producer
Joined: Apr 2014
Posts: 9,371
Likes: 2,736
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
A third of a test since it does not give you volume or spray pattern. But yes, you are right. Short of an ECM failure, 5 is hard to swallow. I would ask how they came to the conclusion. As I learned in math, no working, no credit.
Thread Starter
Advanced
Joined: Jan 2019
Posts: 81
Likes: 15
From: New Braunfels, TX
2020 Corvette of the Year Finalist (stock)
C4 of Year Winner (stock) 2019
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
Thread Starter
Advanced
Joined: Jan 2019
Posts: 81
Likes: 15
From: New Braunfels, TX
2020 Corvette of the Year Finalist (stock)
C4 of Year Winner (stock) 2019
We actually figured out what happened. There was rust in the tank and the fuel pump strainer came off. So it sucked all that junk up. So, we emptied and cleaned tank. Purged the lines and fuel rail, new filter and rebuilt the injectors. Running fine now.