Common Issues with '85 Z28?
Common Issues with '85 Z28?
I'm thinking about getting an '85 Z28 (not IROC
) with a TPI 305 V8 in pristine condition with a rebuilt engine for $2800. What were the common problems with these cars? I would like to know so I can start upgrading parts without having to continually replace others.
) with a TPI 305 V8 in pristine condition with a rebuilt engine for $2800. What were the common problems with these cars? I would like to know so I can start upgrading parts without having to continually replace others. Supreme Member




Joined: Jan 2009
Posts: 2,313
Likes: 115
From: belle fourche,s.d.
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Common Issues with '85 Z28?
if you have rear disc option,the calipers can be trouble.
Tin plated fuse blades can react with brass fuse panel
contacts and and a bad connection can occur-feel for
hot fuses-usually removing, cleaning,and reinstalling
the fuses fixes the problem.
I have heard of cracks occuring at the steering box
mounting.
Can't think of anything else right now...
I have had my '82 since 1990 and it has been very,
very,reliable
Tin plated fuse blades can react with brass fuse panel
contacts and and a bad connection can occur-feel for
hot fuses-usually removing, cleaning,and reinstalling
the fuses fixes the problem.
I have heard of cracks occuring at the steering box
mounting.
Can't think of anything else right now...

I have had my '82 since 1990 and it has been very,
very,reliable
Re: Common Issues with '85 Z28?
There's a 85% chance I'm going out from El Paso to Tuscon this weekend to pick up this Camaro. It needs a tuneup, an oil gasket, alternator and brake pads. I was able to talk the owner down to $2800. Should I hop on this?
http://www.autotrader.com/cars-for-s...ngId=322173918
http://www.autotrader.com/cars-for-s...ngId=322173918
Supreme Member
Joined: Apr 2011
Posts: 1,051
Likes: 0
From: Huntsville, AL
Car: 89 Black IROC-Z convertible
Engine: 305 TBI
Transmission: Auto
Re: Common Issues with '85 Z28?
Why is it listed as a convertible? If that's the correct mileage it's pretty high. "What oil gasket" does it need? Needs tune-up usually means worn engine. On the plus side, It's a good looking car and if it’s really an Arizona car it should be relatively rust free.
Joined: Aug 1999
Posts: 19,282
Likes: 103
From: Lawrence, KS
Car: Met. Silver 85 IROC/Sold
Engine: 350 HO Deluxe (350ci/330hp)
Transmission: T-5 (Non-WC)
Axle/Gears: Limited Slip 3.23's
Re: Common Issues with '85 Z28?
350,000 miles is, well, a lot of miles. I'd have second thoughts.
JamesC
JamesC
Supreme Member
iTrader: (1)
Joined: Nov 2008
Posts: 1,697
Likes: 2
From: Michigan
Car: 86 IROC Z, 92 RS
Engine: 305 4bbl, 305 TBI
Re: Common Issues with '85 Z28?
Could the mileage be a typo? The oil gasket issue would be a red flag. You need to find out what this means. Look at the transmission fluid dipstick. With this many miles the transmission was probably rebuilt, which would be a real plus. When 700r4's are rebuilt they get upgraded. Look at the front tires for uneven wear. The front end probably was or needs rebuilding.
Supreme Member
Joined: Apr 2010
Posts: 4,337
Likes: 29
From: Aurora, OR
Car: 87 IROC Z28
Engine: 355 cid TPI
Transmission: Custom Built 700R4 w/3,500 stall
Axle/Gears: QP fab 9" 3.70 Truetrac
Re: Common Issues with '85 Z28?
I've heard of these cars running 300K+ with no real trouble. The key concerns with this high mileage would of course be condition of the trans, suspension components(especially bushings, ball joints and tie rod ends, steering gear, and rear differential. One thing to pay attention to is how well the car's been maintained, and I don't mean wash and wax jobs. I mean mechanically. Ask for service records and or receipts to verify.
One thing that comes to mind as a big issue with the 85 TPI is the MAF sensor and MAF sensor power module. Both are common failure items and were a one year only design, no longer supported by the OE or most aftermarket parts manufacturers. I hear that A1 Cardone still makes the module(very pricey) which gives me little faith. I have heard of upgrading the EFI system to a newer harness, ECM, and MAF sensor. This sounds expensive. Honestly, unless the car is gorgeous, and then maybe it's worth the trouble, I would not buy a TPI car earlier than 87. 87 was the start of the factory roller cam and uses EFI parts common to all 87 - 89 cars. At least that means there are more of the cars and parts around.
One thing that comes to mind as a big issue with the 85 TPI is the MAF sensor and MAF sensor power module. Both are common failure items and were a one year only design, no longer supported by the OE or most aftermarket parts manufacturers. I hear that A1 Cardone still makes the module(very pricey) which gives me little faith. I have heard of upgrading the EFI system to a newer harness, ECM, and MAF sensor. This sounds expensive. Honestly, unless the car is gorgeous, and then maybe it's worth the trouble, I would not buy a TPI car earlier than 87. 87 was the start of the factory roller cam and uses EFI parts common to all 87 - 89 cars. At least that means there are more of the cars and parts around.
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Re: Common Issues with '85 Z28?
The car does not have 350000 miles. I called the owner about it and he said that the odometer is broken but he estimated 150000 to 200000 miles on it. The car is 275 miles from me so when I go to see it I'm definitely coming back with it. I will ask him tonight if he can send me high resolution pictures of the car as well as the location of the oil leak and transmission fluid level. There's also an '84 sport coupe with a 305 V8, a holley 650 carb, a rebuilt 700r4 transmission here in El Paso but the engine needs to be rebuilt and the interior needs lots of work. The owner is asking 2000 for it.
Sorry this thread went off topic.
Sorry this thread went off topic.
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