Smoking 1990 ZR1
Thread Starter
6th Gear
Joined: Aug 2014
Posts: 6
Likes: 0
Smoking 1990 ZR1
hello and nice to meet you all...
I have a 1990 ZR1. #6 cylinder seems to be leaking fuel from the injector. All the injectors have been replaced. The head gaskets have been replaced as well. we were not positive there was a head gasket issue but replaced during rebuild. white smoke was coming from the right exhaust heavily. smelled like gas. ECM has been gone through. (sent in). spark plugs and wires replaced. Still have smoke issue after all this work.
Note: the work has all been performed by a very well known corvette mechanic in my area. Is there a frame sensor that could be corroding causing this issue???
any ideas on this would be a huge help!
thanks!
I have a 1990 ZR1. #6 cylinder seems to be leaking fuel from the injector. All the injectors have been replaced. The head gaskets have been replaced as well. we were not positive there was a head gasket issue but replaced during rebuild. white smoke was coming from the right exhaust heavily. smelled like gas. ECM has been gone through. (sent in). spark plugs and wires replaced. Still have smoke issue after all this work.
Note: the work has all been performed by a very well known corvette mechanic in my area. Is there a frame sensor that could be corroding causing this issue???
any ideas on this would be a huge help!
thanks!
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Say WHAT?? tbirdsps says water, then you "agree that it's fuel"???
Regardless of what you think your #6 injector is doing (how did you determine that?), white smoke is from water....not fuel. If fuel were the source/cause of your smoke, the smoke would be black....not white.
Regardless of what you think your #6 injector is doing (how did you determine that?), white smoke is from water....not fuel. If fuel were the source/cause of your smoke, the smoke would be black....not white.
Thread Starter
6th Gear
Joined: Aug 2014
Posts: 6
Likes: 0
There is a period after [I agree]... sorry, forgot to capitalize the letter I after the period...
I am trying to say that I agree that in most cases white smoke means water.
I agree that in a rich condition, black smoke is common.
In the condition that I have, there is so much fuel that it is not burning enoughh of the fuel to turn it black. You can actually light the drips of fuel coming from the exhaust.
I have determined that it is #6 because when engine is turned over without spark plug in place, fuel ejects from the cylinder.
I am trying to say that I agree that in most cases white smoke means water.
I agree that in a rich condition, black smoke is common.
In the condition that I have, there is so much fuel that it is not burning enoughh of the fuel to turn it black. You can actually light the drips of fuel coming from the exhaust.
I have determined that it is #6 because when engine is turned over without spark plug in place, fuel ejects from the cylinder.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Well...you can fill a bowl with gas, light it, and it will make BLACK smoke. Can't really get much more fuel (or a richer mixture) than that. I assure you that white smoke is not from too much fuel. Anyway, if you have raw fuel coming from the exhaust and from cylinder #6 with the spark plug out, then you have a problem with #6 injector.
What happens if you unplug the electrical connector from #6 injector? Are you still getting raw fuel from that spark plug hole?
What happens if you unplug the electrical connector from #6 injector? Are you still getting raw fuel from that spark plug hole?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
Mount a gauge on the rails. If the Injector is dumping, it will loose all its pressure. Key on, engine off. If ones bad, Replace them all, then move on. Common problem and Expensive. Also is your oil level rising? The oil smell like gas? Why did the heads come off in the first place? They should of went to the machine shop to be disassembled and Magnafluxed and freshed up. Why wasn't that done? Then you would be where your at right now. You can't play with these things because you end up doing things over and over and a gas wash on the motor isn't good because it can cause expensive problems in the bottom end
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
http://forums.corvetteforum.com/c4-z...injectors.html
http://www.zr1.net/forum/showthread.php?p=148378
http://www.zr1.net/forum/showthread.php?p=148378
Last edited by cudamax; Aug 20, 2014 at 05:28 PM.
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
Good luck!
Thread Starter
6th Gear
Joined: Aug 2014
Posts: 6
Likes: 0
There was fuel getting in the oil. The heads were pulled during the rebuild. The mechanic strongly felt like this was a water issue and not fuel. (head gasket most likely). This turned out to not be a water issue. The heads were freshened up and the engine rebuilt. The gas wash is a major concern and I agree that the engine should not be run due to this. Mechanic was not available yesterday. I will report back the injector troubleshooting sequence he used when I can.
thank you to everyone for the feedback and I will keep you posted.
thank you to everyone for the feedback and I will keep you posted.
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
Race Director
Joined: Feb 2002
Posts: 11,622
Likes: 1,056
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
If you are sure its the injector just unplug it and see if it stops. Be sure to also unplug the secondary injector in case its the issue. If the fuel is the cause of the white smoke it should stop, now the motor will run ruff on 7 cylinders. You may also want to drain the oil and check for contamination gas or water.
If you still have white smoke it was not the issue.
If you still have white smoke it was not the issue.
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
Wait a minute. Your mechanic pulled the heads because he thought this smoking problem was a head gaskt problem? or what?
Did u go to a mechanic because it had white smoke coming from the tail pipe? and he said he wanted to pull the heads thinking it was a head gaskt?, if so did u also have fuel at the same time in the oil? or did that happen after the heads were pulled?
Because I'm thinking you u went somewhere for a Diagnosis and he just pulled the heads and just inspected the head gaskt's and thought they looked good, then went on to freshen up the valve train and didn't strip them down and send them out for Magnafluxing or other tests and he didn't look into it far enough. Because u can't really see all the time just with ur naked eye cracks in Aluminum or pin holes.
http://www.goodson.com/blog/2012/01/...ack-detection/
Has this motor overheated? had a coolant leak? then overheated? Was it and if so How long was it run hot?
Anyways if he thought it was a water Issue and pulled it all apart and then afterwards you are still where u were to begin with minus a lot of Cash. I'd be pissed and asking why the heads were not inspected completely to rule out and cracks or pin hole and or looking to find someone else to do the work that can get into it and come out with the thing fixed, the first time. IMO
Did u go to a mechanic because it had white smoke coming from the tail pipe? and he said he wanted to pull the heads thinking it was a head gaskt?, if so did u also have fuel at the same time in the oil? or did that happen after the heads were pulled?
Because I'm thinking you u went somewhere for a Diagnosis and he just pulled the heads and just inspected the head gaskt's and thought they looked good, then went on to freshen up the valve train and didn't strip them down and send them out for Magnafluxing or other tests and he didn't look into it far enough. Because u can't really see all the time just with ur naked eye cracks in Aluminum or pin holes.
http://www.goodson.com/blog/2012/01/...ack-detection/
Has this motor overheated? had a coolant leak? then overheated? Was it and if so How long was it run hot?
Anyways if he thought it was a water Issue and pulled it all apart and then afterwards you are still where u were to begin with minus a lot of Cash. I'd be pissed and asking why the heads were not inspected completely to rule out and cracks or pin hole and or looking to find someone else to do the work that can get into it and come out with the thing fixed, the first time. IMO
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah