90 ZR1: Oh crud, did I break it? - ZR-1 Net Registry Forums

GTOger · 11-25-2010

Happy Thanksgiving everyone. The wife and I decided to take the ZR1 to the family turkey extravaganza about 15 miles up the road. It ran great all the way there and half-way back. At the half way point, things got ugly.

All of a sudden there was a loss of power and the engine was running rough. Definitely not hitting on all cylinders. Pulled up at a stop light and it didn't really want to stay running. Without giving it little throttle bursts, it would have died.

There was no "drama" leading up to this. I hadn't been hot-rodding. There wasn't any bang or other indication. Gauges remained normal and no indications on the cluster.

At the next light I saw that there was smoke coming out the back when I gave a little gas.

We limped home and into the garage and I shut it down. It smells to me like there's unburned fuel in the exhaust. We unloaded the leftovers (mmmm... turkey....) and then came out and lifted the hood. No signs of external trauma. Nothing leaking, seeping or oozing. Oil is still full (and clean).

Started her up again and it continued to run like crud. White smoke from the exhaust.

Just under 28k miles. No mods save for a B&B exhaust and K&N filter from previous owner.

I'm trying to reassure the wife that the car we got 3 weeks ago will be alright again. I know the injectors are notorious on these cars, but maybe it's spark.

Any recommendations on where to start? Maybe this looks familiar to somebody.

GTOger · 11-25-2010

Blown head gasket? Ew.

The radiator over flow bottle has water in it.... not much. It's at the "cold" line. Engine's been off for about an hour. Garage is about 45 deg.

What else should I look for to confirm/deny it? And I guess next question... how hard is it to replace (find?) an LT5 head gasket? <ducking>

GOLDCYLON · 11-25-2010

Quote:

Originally Posted by GTOger

What else should I look for to confirm/deny it? And I guess next question... how hard is it to replace (find?) an LT5 head gasket? <ducking>

Shaving cream milky sustance on the oil dipstick. About $89.00 per side on Ebay

GTOger · 11-25-2010

Thanks Xfire751. I guess next I will need to figure out how to pull the plugs on this beast. They look well buried, and I have very little experience with this car. Dumb question: what's the "IH" in "IH to head interface"? Lucky for me... there's a shop manual in the back!

GOLDCYLON · 11-25-2010

Quote:

Originally Posted by GTOger

Thanks Xfire751. I guess next I will need to figure out how to pull the plugs on this beast. They look well buried, and I have very little experience with this car. Dumb question: what's the "IH" in "IH to head interface"? Lucky for me... there's a shop manual in the back!

IH ="s Injector Housing

Jagdpanzer · 11-25-2010

Do you smell gas and does the smoke come out of only one exhaust pipe? If so could be a blown fuel injector. If it is you will quickly burn out the cat on the side with the bad injector. Very same thing happened to ZZZZZR-1 David.

bdw18_123 · 11-26-2010

You might want to also check the MAP sensor hose. If it comes off, the car will run like crap.

Pete · 11-26-2010

Quote:

Originally Posted by bdw18_123

You might want to also check the MAP sensor hose. If it comes off, the car will run like crap.

Also check MAP if filled with oil.

Pete

GTOger · 11-25-2010

Quote:

Originally Posted by GTOger

Dumb question: what's the "IH" in "IH to head interface"? Lucky for me... there's a shop manual in the back!

Duh. Injector Housing. Got my service manual out and I'm going to study. Thanks gents for the input. Anything else you think I ought to know, hip me to it. I'm grateful for the knowledge here.

GTOger · 11-25-2010

Man, you guys are QUICK on this board. Not used to that!

Goldcylon, the oil dipstick looked nice and normal to me and I checked within 2 minutes of pulling in the garage.

I may wait till daylight for more digging since lighting in my garage pretty sell stinks.

11-25-2010	#1
GTOger Join Date: Nov 2010 Location: Dallas, TX Posts: 198	90 ZR1: Oh crud, did I break it? Happy Thanksgiving everyone. The wife and I decided to take the ZR1 to the family turkey extravaganza about 15 miles up the road. It ran great all the way there and half-way back. At the half way point, things got ugly. All of a sudden there was a loss of power and the engine was running rough. Definitely not hitting on all cylinders. Pulled up at a stop light and it didn't really want to stay running. Without giving it little throttle bursts, it would have died. There was no "drama" leading up to this. I hadn't been hot-rodding. There wasn't any bang or other indication. Gauges remained normal and no indications on the cluster. At the next light I saw that there was smoke coming out the back when I gave a little gas. We limped home and into the garage and I shut it down. It smells to me like there's unburned fuel in the exhaust. We unloaded the leftovers (mmmm... turkey....) and then came out and lifted the hood. No signs of external trauma. Nothing leaking, seeping or oozing. Oil is still full (and clean). Started her up again and it continued to run like crud. White smoke from the exhaust. Just under 28k miles. No mods save for a B&B exhaust and K&N filter from previous owner. I'm trying to reassure the wife that the car we got 3 weeks ago will be alright again. I know the injectors are notorious on these cars, but maybe it's spark. Any recommendations on where to start? Maybe this looks familiar to somebody. __________________ [B]1990 Corvette ZR-1 (#1930) Red/Black, Stock Engine, Henderson Performance custom ECM, FIC Injectors, B&B exhaust, Kenwood DNX6160[/B] Other Rides: 1992 Pontiac Firehawk (#010), 1967 Pontiac GTO 1998 Porsche 968, 2000 Harley Davidson FXST 1986 Pontiac Trans Am, 1931 Ford Model A Tudor Deluxe

11-25-2010	#2
GTOger Join Date: Nov 2010 Location: Dallas, TX Posts: 198	Re: 90 ZR1: Oh crud, did I break it? Blown head gasket? Ew. The radiator over flow bottle has water in it.... not much. It's at the "cold" line. Engine's been off for about an hour. Garage is about 45 deg. What else should I look for to confirm/deny it? And I guess next question... how hard is it to replace (find?) an LT5 head gasket? <ducking> __________________ [B]1990 Corvette ZR-1 (#1930) Red/Black, Stock Engine, Henderson Performance custom ECM, FIC Injectors, B&B exhaust, Kenwood DNX6160[/B] Other Rides: 1992 Pontiac Firehawk (#010), 1967 Pontiac GTO 1998 Porsche 968, 2000 Harley Davidson FXST 1986 Pontiac Trans Am, 1931 Ford Model A Tudor Deluxe

11-25-2010	#4
GTOger Join Date: Nov 2010 Location: Dallas, TX Posts: 198	Re: 90 ZR1: Oh crud, did I break it? Thanks Xfire751. I guess next I will need to figure out how to pull the plugs on this beast. They look well buried, and I have very little experience with this car. Dumb question: what's the "IH" in "IH to head interface"? Lucky for me... there's a shop manual in the back! __________________ [B]1990 Corvette ZR-1 (#1930) Red/Black, Stock Engine, Henderson Performance custom ECM, FIC Injectors, B&B exhaust, Kenwood DNX6160[/B] Other Rides: 1992 Pontiac Firehawk (#010), 1967 Pontiac GTO 1998 Porsche 968, 2000 Harley Davidson FXST 1986 Pontiac Trans Am, 1931 Ford Model A Tudor Deluxe

11-25-2010	#6
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Re: 90 ZR1: Oh crud, did I break it? Do you smell gas and does the smoke come out of only one exhaust pipe? If so could be a blown fuel injector. If it is you will quickly burn out the cat on the side with the bad injector. Very same thing happened to ZZZZZR-1 David.

11-26-2010	#7
bdw18_123 Join Date: Apr 2009 Location: Prather, CA Posts: 809	Re: 90 ZR1: Oh crud, did I break it? You might want to also check the MAP sensor hose. If it comes off, the car will run like crap. __________________ [IMG]http://i13.photobucket.com/albums/a292/bdw18_123/_zr1netforumsigphoto.jpg[/IMG][B] 1990 Corvette ZR-1 [/B][I] White/Flame Red, #2299, mostly stock, 144K miles.[/I] -Cams timed to the '93-'95 405HP LT5 stock timing. -IAT sensor relocated to below front bumper. -Haibeck hoops installed in airduct. -OBX cat-back exhaust. [COLOR=DarkRed][B](SOLD - December 2012 [/B][/COLOR][COLOR=DarkRed][B]:hello:)[/B][/COLOR] 1993 Corvette Coupe Black/Black, 6-speed (SOLD - October 2009 :hello:)