90 Vette Intake Gasket problem?
Thread Starter
Heel & Toe
Joined: Mar 2013
Posts: 17
Likes: 0
90 Vette Intake Gasket problem?
Hello,
I have a 90 vette 5.7 and I believe it has an intake gasket leak. I have taken the valve covers off and taken some pics so you can see. It looses coolant but not externally and the oil is a little milky from the dipstick. I have heard that the intakes are dry and cannot cause this but not sure about that? The cars runs like a beast but does have problem like it wants to die and sometimes will stall after driving it pretty good when completely stopped but will stay running if switched into neutral so I do not think head gasket but would like others opinions and maybe someone has had same problem.
Thanks
here is link to photo bucket it wont let me attach
http://s305.photobucket.com/user/toy...y/Vette?page=1
Here are the compression test results
Driver Bank passenger bank
1.168 1.168
2.155 2. 169
3. 165 3.160
4. 138 4. 150
The oddball cylinder is at 138 could have been a bad reading this is the number 7 cylinder I believe?
Any thoughts on this thread anybody
Thanks for your input.
I have a 90 vette 5.7 and I believe it has an intake gasket leak. I have taken the valve covers off and taken some pics so you can see. It looses coolant but not externally and the oil is a little milky from the dipstick. I have heard that the intakes are dry and cannot cause this but not sure about that? The cars runs like a beast but does have problem like it wants to die and sometimes will stall after driving it pretty good when completely stopped but will stay running if switched into neutral so I do not think head gasket but would like others opinions and maybe someone has had same problem.
Thanks
here is link to photo bucket it wont let me attach
http://s305.photobucket.com/user/toy...y/Vette?page=1
Here are the compression test results
Driver Bank passenger bank
1.168 1.168
2.155 2. 169
3. 165 3.160
4. 138 4. 150
The oddball cylinder is at 138 could have been a bad reading this is the number 7 cylinder I believe?
Any thoughts on this thread anybody
Thanks for your input.
Melting Slicks
Joined: Sep 2010
Posts: 2,422
Likes: 202
yikes you are not within 10% on your # 4
what the heck kind of system do you have?? what happen to
LB 1357
RB 2468
and NO. the TPI intake flows coolant in the front passages. the rear is blocked.
The 92 - 96 C4 LT1 <> 93 - 97 other cars LT1 does not have coolant flowing through the intake.
what the heck kind of system do you have?? what happen to
LB 1357
RB 2468
and NO. the TPI intake flows coolant in the front passages. the rear is blocked.
The 92 - 96 C4 LT1 <> 93 - 97 other cars LT1 does not have coolant flowing through the intake.
Last edited by THE 383 admiral; Mar 23, 2013 at 11:19 PM.
Thread Starter
Heel & Toe
Joined: Mar 2013
Posts: 17
Likes: 0
yikes you are not within 10% on your # 4
what the heck kind of system do you have?? what happen to
LB 1357
RB 2468
and NO. the TPI intake flows coolant in the front passages. the rear is blocked.
The 92 - 96 C4 LT1 <> 93 - 97 other cars LT1 does not have coolant flowing through the intake.
what the heck kind of system do you have?? what happen to
LB 1357
RB 2468
and NO. the TPI intake flows coolant in the front passages. the rear is blocked.
The 92 - 96 C4 LT1 <> 93 - 97 other cars LT1 does not have coolant flowing through the intake.
Also Not real familiar with the LT1 its a friends car and I am trying to figure this out for him. Not sure what LB1357 and RB2468 are?
this is a 1990 as well.
Also on the compression I may run again especially on the number 4 but the thing will **** and get no drivability issues when hammering down and running only issue is at idle which I feel is something else seeing how the PCV valve is caked up as well. Also the compression test was done without opening to WOT (I forgot oops but do not think that will matter?)
Thanks For your reply
Racer
Joined: Aug 2012
Posts: 279
Likes: 2
From: Las Vegas Nevada
I can't say anything about the coolant...
But when I did a compression test on my 85 I got between 160 and 170 on all but my #5 cylinder, which got about 135. Say what you guys want, I ended up spraying about a cup of WD40 into the cylinder through the spark plug hole and let it sit overnight. Ran another compression test the next day and I got 170. I did this originally because I was told I had a blown head gasket, but the results made me laugh. Turned out to be a vacuum leak from the intake manifold. Spray some water around all the edges of the intake, and near the injectors while the engine's running. If your idle changes, or the car almost dies, you need a new set of gaskets for the WHOLE intake because you might as well do it for the future. My kit also came with new O-rings for the injectors but mine were still new.
But when I did a compression test on my 85 I got between 160 and 170 on all but my #5 cylinder, which got about 135. Say what you guys want, I ended up spraying about a cup of WD40 into the cylinder through the spark plug hole and let it sit overnight. Ran another compression test the next day and I got 170. I did this originally because I was told I had a blown head gasket, but the results made me laugh. Turned out to be a vacuum leak from the intake manifold. Spray some water around all the edges of the intake, and near the injectors while the engine's running. If your idle changes, or the car almost dies, you need a new set of gaskets for the WHOLE intake because you might as well do it for the future. My kit also came with new O-rings for the injectors but mine were still new.
Last edited by Ziggy91; Mar 24, 2013 at 11:13 PM.
Burning Brakes
Joined: Nov 2004
Posts: 897
Likes: 12
From: Land of Whiskey Rebels, PA
Glad you found the problem and that it wasn't something serious. Good job.
By the way, it goes like this:
Driver's side, front to back, #'s 1-3-5-7
Passenger's side, front to back, #'s 2-4-6-8
Also, if you buy a set of injectors from fuelinjectionconnection.com, you will get a new set of gaskets and o-rings with them. Just in case you need them in the future.
By the way, it goes like this:
Driver's side, front to back, #'s 1-3-5-7
Passenger's side, front to back, #'s 2-4-6-8
Also, if you buy a set of injectors from fuelinjectionconnection.com, you will get a new set of gaskets and o-rings with them. Just in case you need them in the future.
