Help in tuning a 1988
Thread Starter
Racer
Joined: Dec 2003
Posts: 454
Likes: 0
From: Double Oak TX
Help in tuning a 1988
Got a bud with a 1988 C4 that for the most part has very few miles on it and mostly stored for the last 10 years. It may get driven 500 mile per year. He wanted me to help tune it which I'll gladly do; but the problem is I know the LTx stuff like the back of my hand, but just never worked on a tuned port and am wondering if I'm touching all the bases.
What I have planned:
• Replace the air filter
• New factory wires (it's 100% original so it makes sense to keep it that way)
• New plugs….. Was going to use NKG TR55's….OK?? Or is there something special I need to know about plugs for one.
• New 02 sensors
• Clean the injectors
• Check cylinder pressure
• Check fuel pressure
Besides your basic overall inspection, anything else that I should be aware of?
What I have planned:
• Replace the air filter
• New factory wires (it's 100% original so it makes sense to keep it that way)
• New plugs….. Was going to use NKG TR55's….OK?? Or is there something special I need to know about plugs for one.
• New 02 sensors
• Clean the injectors
• Check cylinder pressure
• Check fuel pressure
Besides your basic overall inspection, anything else that I should be aware of?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Instead of replacing the O2 sensor (only one in the LH Y pipe) I prefer to jumper ALDL pins A&B (upper right), start the engine and allow it to warm up while watching the SES light flashes. If all is well with the coolant temp sensor & O2 sensor the flashes will slow from about 2Hz to 1Hz and be of equal on & off duration after about 2 minutes.
Also change the fuel filter under the RH front of the car, in the fuel line near the starter motor.
If fluids haven't been changed on a regular basis due to low mileage consider changing coolant, oil & filter, tanny fluid & filter, brake fluid flush and chassis lube.
Also check the rubber for hardening; if so replace all tires with GY Eagle HP Ultra Plus which are very close to original rubber and a very good tire.
Work some GM silicone lube into all weather stripping to extend life and maintain pliability.
Instead of doing a cylinder check, just take it out for a drive and watch fuel mileage on a flat road with cruize set. If he has stock 2.59 gears (with an A4 tranny) mileage should be close to 30mpg at steady 60mph. In which case all is well with compresion, etc.
Also change the fuel filter under the RH front of the car, in the fuel line near the starter motor.
If fluids haven't been changed on a regular basis due to low mileage consider changing coolant, oil & filter, tanny fluid & filter, brake fluid flush and chassis lube.
Also check the rubber for hardening; if so replace all tires with GY Eagle HP Ultra Plus which are very close to original rubber and a very good tire.
Work some GM silicone lube into all weather stripping to extend life and maintain pliability.
Instead of doing a cylinder check, just take it out for a drive and watch fuel mileage on a flat road with cruize set. If he has stock 2.59 gears (with an A4 tranny) mileage should be close to 30mpg at steady 60mph. In which case all is well with compresion, etc.
Thread Starter
Racer
Joined: Dec 2003
Posts: 454
Likes: 0
From: Double Oak TX
Instead of replacing the O2 sensor (only one in the LH Y pipe) I prefer to jumper ALDL pins A&B (upper right), start the engine and allow it to warm up while watching the SES light flashes. If all is well with the coolant temp sensor & O2 sensor the flashes will slow from about 2Hz to 1Hz and be of equal on & off duration after about 2 minutes.
Also change the fuel filter under the RH front of the car, in the fuel line near the starter motor.
If fluids haven't been changed on a regular basis due to low mileage consider changing coolant, oil & filter, tanny fluid & filter, brake fluid flush and chassis lube.
Also check the rubber for hardening; if so replace all tires with GY Eagle HP Ultra Plus which are very close to original rubber and a very good tire.
Work some GM silicone lube into all weather stripping to extend life and maintain pliability.
Instead of doing a cylinder check, just take it out for a drive and watch fuel mileage on a flat road with cruize set. If he has stock 2.59 gears (with an A4 tranny) mileage should be close to 30mpg at steady 60mph. In which case all is well with compresion, etc.
Also change the fuel filter under the RH front of the car, in the fuel line near the starter motor.
If fluids haven't been changed on a regular basis due to low mileage consider changing coolant, oil & filter, tanny fluid & filter, brake fluid flush and chassis lube.
Also check the rubber for hardening; if so replace all tires with GY Eagle HP Ultra Plus which are very close to original rubber and a very good tire.
Work some GM silicone lube into all weather stripping to extend life and maintain pliability.
Instead of doing a cylinder check, just take it out for a drive and watch fuel mileage on a flat road with cruize set. If he has stock 2.59 gears (with an A4 tranny) mileage should be close to 30mpg at steady 60mph. In which case all is well with compresion, etc.
Thank you very much. It's a 4+3 car but I'm sure it should be close. Also nice tip on the GM silicone lube and I'll try some on my car.
Thanks again!!
Thread Starter
Racer
Joined: Dec 2003
Posts: 454
Likes: 0
From: Double Oak TX
Instead of replacing the O2 sensor (only one in the LH Y pipe) I prefer to jumper ALDL pins A&B (upper right), start the engine and allow it to warm up while watching the SES light flashes. If all is well with the coolant temp sensor & O2 sensor the flashes will slow from about 2Hz to 1Hz and be of equal on & off duration after about 2 minutes.
Instead of doing a cylinder check, just take it out for a drive and watch fuel mileage on a flat road with cruize set. If he has stock 2.59 gears (with an A4 tranny) mileage should be close to 30mpg at steady 60mph. In which case all is well with compresion, etc.
Instead of doing a cylinder check, just take it out for a drive and watch fuel mileage on a flat road with cruize set. If he has stock 2.59 gears (with an A4 tranny) mileage should be close to 30mpg at steady 60mph. In which case all is well with compresion, etc.
Guess I'm a certified member of the "frequent dyno club" and my car more than likely sees 4-6 dyno tuning sessions per year. Usually redo the tune for warm weather in the spring and cool weather in the fall or when making changes or after problems. As a rule of thumb, I'll replace the 02's probably yearly as I've found the car appears to make it's best power with fresh 02's and also seems to run smoother with frequent change. Also running quite a bit of cam and compression so my 02's may see a little more wear than most, but I've found it does help.
Just old school on checking compression. If you already have the plugs out and you got a compression guage, it's just not that much work in my opinion and is a pretty good objective indicator.
