Opinions on this ‘91 please.

[B17 Crew]

Went to look at this ‘91 this afternoon, it’s number 360. It’s a one owner car, unmodified with the exceptions of an update to ‘92-‘96 exhaust and Hella headlights. The body is straight, panel fit is very good, I could not find evidence of an accident. Original window sticker and some other documentation come with the car. I was unable to drive it this visit, it was heavily blocked in by other cars in the back of the showroom. I was able to start/rev the car. Was able to talk to the owner of the dealership, he did not try to mislead me and appeared to be a straight shooter as well as knowledgeable about Corvettes.

Link to Z:
http://www.arenamotor.com/1991-Chevr...043201/6403086

What it needs:

• New tires all around.
• Headlight motors continue to run for about 3 seconds after turning lights on/off.
• Driver’s side bolster motor sounded “weak”.
• Professional buff to remove fine scratches in clearcoat
• Steering column needs attention. Has play in it (this may be from the driver using it to ingress/egress the car).
• Driver side leather bolsters heavily worn.
• Grey triangular tabs missing (by power seat controls).

What I noticed:

• LT-5 engine cranking takes several seconds longer than my LT-4.
• There was a vibration with an audible “bumping sound” at start up that subsided after about 20 seconds. Not sure if vibration was from engine or clutch.
• Pre ‘94 type style seats are not as comfortable/supportive as ‘94-‘96 seats (IMHO).
• This ‘91 is not as tight/sold in regards to interior fit and finish as my ‘96 LT-4 which has 60K miles on it, the Z has 74K miles.
• It has slight delimitation on windshield but did not affect outward vision.
• Exhaust tips are not aligned, seem off-angle. Can be seen in rear photos of car.

My main concerns were the vibration/audible “bumping sound” at start up and headlight motors continuing to run which make me question if the car has electrical gremlins. Dealer has it listed for 20k but will take 17k. I look forward to and would appreciate any input on the car. Thank you.


B17Crew

[efnfast]

If it's mechanically sound, looks pretty good at 17K. If there are gremlins, FBI crew is not that far away.

[G8nightman]

If you do your own work the headlights is a nonissue about 50 bucks in parts needed to fix.


Sent from my iPhone using ZR-1 Net Registry

[Ccmano]

Originally Posted by B17 Crew

Went to look at this ‘91 this afternoon, it’s number 360. It’s a one owner car, unmodified with the exceptions of an update to ‘92-‘96 exhaust and Hella headlights. The body is straight, panel fit is very good, I could not find evidence of an accident. Original window sticker and some other documentation come with the car. I was unable to drive it this visit, it was heavily blocked in by other cars in the back of the showroom. I was able to start/rev the car. Was able to talk to the owner of the dealership, he did not try to mislead me and appeared to be a straight shooter as well as knowledgeable about Corvettes.

Link to Z:
http://www.arenamotor.com/1991-Chevr...043201/6403086

What it needs:

• New tires all around.
• Headlight motors continue to run for about 3 seconds after turning lights on/off.
• Driver’s side bolster motor sounded “weak”.
• Professional buff to remove fine scratches in clearcoat
• Steering column needs attention. Has play in it (this may be from the driver using it to ingress/egress the car).
• Driver side leather bolsters heavily worn.
• Grey triangular tabs missing (by power seat controls).

What I noticed:

• LT-5 engine cranking takes several seconds longer than my LT-4. Normal, they are designed to crank longer
• There was a vibration with an audible “bumping sound” at start up that subsided after about 20 seconds. Not sure if vibration was from engine or clutch. A number of possibilities could be some or all. Bad injector, bad dual mass flywheel, coil issue or all of the above. Mostly likely bad injector causing the flywheel it make noise.
• Pre ‘94 type style seats are not as comfortable/supportive as ‘94-‘96 seats (IMHO).
• This ‘91 is not as tight/sold in regards to interior fit and finish as my ‘96 LT-4 which has 60K miles on it, the Z has 74K miles.yup, they made some progress in 5 years
• It has slight delimitation on windshield but did not affect outward vision.Normal, ZR-1 uses a special windshield.
• Exhaust tips are not aligned, seem off-angle. Can be seen in rear photos of car. Those are later version mufflers but is fixable.

My main concerns were the vibration/audible “bumping sound” at start up and headlight motors continuing to run which make me question if the car has electrical gremlins. Dealer has it listed for 20k but will take 17k. I look forward to and would appreciate any input on the car. Thank you.


B17Crew

Welcome to the addiction...

Answered some of your questions above.

Here a list of things to look at. I'm sure I missed few but here you go. Frankly, to me, $17k is high for a 91 in this condition and miles that potentially needs work.

Known issues for the ZR-1, some related to higher miles some not.
Injectors - 90-92 must be replaced.
Vacuum leaks to the secondary throttle system.
Secondaries operable?
Ingnition coils and wires replaced?
Timing chain noise at start (normal to a some degree on 90's)
Starter, does the car start consistently
Oil leaks especially the pan and oil cooler lines
Fuel pumps, have they ever been replaced?
Is it throwing any engine, abs or body codes (SES light on?,multiple possibilities here)
Are any DIC lights on. (Multiple possibilities here as well)
Is the adjustable shocks system working
Windshield delamination
A/C functionality (compressor is unique to the Z, cooling capacity lower)
Power switch functionality and keys (are there 2)
Transmission syncro's, (first gear is always noisy) shifter alignment can mimick synco problems.
Clutch functionality (they all let in high, was it ever changed)
Egr system on later models
Engine mounts

C4 Issues
Head lights operable
Radiator blocked or simply clogged, electric fans operable
Wheel bearings
Suspension bushings
Condition of all door, top and hatch seals
Glass roof cracking
Instrument cluster functionality especially the tach (tends to read high with age) also note the lighting of the cluster.
DIC button functionality
Steering wheel excessive movement
Radio functionality (especially speaker amps) and antenna
Sport seat functionality (transmission, switches, pumps and bladders)
Door window switches
Door window lifter and internal rattles
Fuel tank bladder collapse (results in small capacity)
Differential noise (whine)

Good luck
H

[B17 Crew]

Originally Posted by efnfast

If it's mechanically sound, looks pretty good at 17K. If there are gremlins, FBI crew is not that far away.

Thank you for mentioning the FBI, I have read about them here on the Registry. I asked the owner of the dealership if he knew of any mechanics in our area that would be able to service the engine if something were to occur beyond my skill level. There is only one mechanic in our area he recommends. He is at Buyers Chevrolet, this is where the car has been serviced its entire life by the original owner. The other option is Marc Haibeck, about a 6 hour drive from where I live.

B17Crew

[B17 Crew]

Originally Posted by G8nightman

If you do your own work the headlights is a nonissue about 50 bucks in parts needed to fix.


Sent from my iPhone using ZR-1 Net Registry

Thank you, I am more inclined to do my own work, the repair sounds as if it would be something I could take care of.

B17Crew

[B17 Crew]

Originally Posted by Ccmano

Welcome to the addiction...

Answered some of your questions above.

Here a list of things to look at. I'm sure I missed few but here you go. Frankly, to me, $17k is high for a 91 in this condition and miles that potentially needs work.

Known issues for the ZR-1, some related to higher miles some not.
Injectors - 90-92 must be replaced.
Vacuum leaks to the secondary throttle system.
Secondaries operable?
Ingnition coils and wires replaced?
Timing chain noise at start (normal to a some degree on 90's)
Starter, does the car start consistently
Oil leaks especially the pan and oil cooler lines
Fuel pumps, have they ever been replaced?
Is it throwing any engine, abs or body codes (SES light on?,multiple possibilities here)
Are any DIC lights on. (Multiple possibilities here as well)
Is the adjustable shocks system working
Windshield delamination
A/C functionality (compressor is unique to the Z, cooling capacity lower)
Power switch functionality and keys (are there 2)
Transmission syncro's, (first gear is always noisy) shifter alignment can mimick synco problems.
Clutch functionality (they all let in high, was it ever changed)
Egr system on later models
Engine mounts

C4 Issues
Head lights operable
Radiator blocked or simply clogged, electric fans operable
Wheel bearings
Suspension bushings
Condition of all door, top and hatch seals
Glass roof cracking
Instrument cluster functionality especially the tach (tends to read high with age) also note the lighting of the cluster.
DIC button functionality
Steering wheel excessive movement
Radio functionality (especially speaker amps) and antenna
Sport seat functionality (transmission, switches, pumps and bladders)
Door window switches
Door window lifter and internal rattles
Fuel tank bladder collapse (results in small capacity)
Differential noise (whine)

Good luck
H

Wow! Thank you, this is a great checklist. The noise upon start up, I don’t know if it was generated by the timing chain or not. I currently do not have enough experience with the LT-5 to know if what I heard was normal or not. My take is the sound and vibration were not normal operating characteristics of the LT-5.

I figured the dealer purchased the car from the original owner somewhere in the 14k range. Thank you for your direction on pricing as well!

B17Crew

[efnfast]

Originally Posted by B17 Crew

Thank you for mentioning the FBI, I have read about them here on the Registry. I asked the owner of the dealership if he knew of any mechanics in our area that would be able to service the engine if something were to occur beyond my skill level. There is only one mechanic in our area he recommends. He is at Buyers Chevrolet, this is where the car has been serviced its entire life by the original owner. The other option is Marc Haibeck, about a 6 hour drive from where I live.

B17Crew

Some of the best help for this car right in the Chicago area.

[Ccmano]

Originally Posted by efnfast

Some of the best help for this car right in the Chicago area.

Agreed... it's your good fortune to be close to Haibeck and the FBI crew. I consider myself blessed to have been part of the Chicago FBI and maintain my honorary status.
H

[Ccmano]

Originally Posted by B17 Crew

Wow! Thank you, this is a great checklist. The noise upon start up, I don’t know if it was generated by the timing chain or not. I currently do not have enough experience with the LT-5 to know if what I heard was normal or not. My take is the sound and vibration were not normal operating characteristics of the LT-5.

I figured the dealer purchased the car from the original owner somewhere in the 14k range. Thank you for your direction on pricing as well!

B17Crew

Chain rattle on startup is a distinct rattle or clatter not a vibration, bumping or rough running. 91's are not generally inclined to chain rattle. Rough running and knocking (similar to rod knock) is almost always injectors causing the flywheel to knock. Hard to say about this one without experiencing it.
H