Rescue ‘87 needs love-Please help
Thread Starter
Intermediate
Joined: Feb 2022
Posts: 37
Likes: 5
From: Vancouver, WA
Rescue ‘87 needs love-Please help
Greetings gents✋ New to the forum and C4 ownership. Recently rescued a red 87 convertible. Not sure how long she sat. I want to enjoy restoring her. I don’t have a mechanical background but am reasonably smart and enjoy working with my hands. Would appreciate experienced help. I plan to replace a lot of things for fun and because I’m pretty sure the last guy didn’t do anything. First things first. She starts fine, idles at 900, and revs great just sitting but exhaust is very strong/rich. When driving, she sputters and pops under acceleration at about 3000 RPMs. Have replaced faulty alternator, plugs, plug wires, cap, rotor, coil, O2 sensor, and fuel filter. Also cleaned the MAF and throttle body with approved cleaners. No codes but issue still exists. Have also ordered an FSM. What would you gents suggest I do next? Thanks in advance for your patience, kindness, and help.
Last edited by JstAskin; Feb 7, 2022 at 04:15 AM. Reason: Edited so post will be placed with posts listing similar issues
Pro
Joined: Feb 2009
Posts: 655
Likes: 164
From: Vancouver Washington
My 86 sat for 5 years and the fuel injectors were gummed up. ran a can of seafoam thru the gas tank and they all cleared up and the stinky exhaust went away. Might check fuel pressure as well.
First things first though.........get a factory service manual.
First things first though.........get a factory service manual.
Thread Starter
Intermediate
Joined: Feb 2022
Posts: 37
Likes: 5
From: Vancouver, WA
Jazfe
Thanks for responding. Have added Seafoam. FSM already on its way. Also buying a fuel pressure tester and multimeter. Quick question. Before using Seafoam were you having acceleration issues?
Appreciate your help.
Thanks for responding. Have added Seafoam. FSM already on its way. Also buying a fuel pressure tester and multimeter. Quick question. Before using Seafoam were you having acceleration issues?
Appreciate your help.
Team Owner
Joined: Dec 2012
Posts: 30,427
Likes: 1,609
From: Outside the Quick Stop N.J.
Start with draining out as much of the old fuel as possible. You may get lucky with trying to clean the injectors.
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Thread Starter
Intermediate
Joined: Feb 2022
Posts: 37
Likes: 5
From: Vancouver, WA
Thanks for your help👍
Team Owner
Joined: Dec 2012
Posts: 30,427
Likes: 1,609
From: Outside the Quick Stop N.J.
You can pull the injectors out and test them by putting each one in an individual container so you can observe the spray pattern, but that can get involved.
Do you have access to a scanner ? Even though there are no codes, reading the live data may shed some light on your problem. I would update your location, there might be a member close by that could help you out.
Pro
Joined: Mar 2007
Posts: 595
Likes: 355
From: Mt Prospect IL
2025 C4 of the Year Finalist - Unmodified
Many good suggestions here. I am a fan of less is more. Before you start pulling parts looking for a problem, I’m going with Patsgarage. Dump the old fuel and get fresh fuel and a good injector cleaner ie, Seafoam or Techron. I prefer Techron but it doesn’t matter, just use one. Second, double check your work, very easy to mix plug wires. Also, while it’s idling, lightly tap on MAF. See if engine stumbles. Could be bad. Hope it all sorts itself out and you are on the road soon.
Thread Starter
Intermediate
Joined: Feb 2022
Posts: 37
Likes: 5
From: Vancouver, WA
Many good suggestions here. I am a fan of less is more. Before you start pulling parts looking for a problem, I’m going with Patsgarage. Dump the old fuel and get fresh fuel and a good injector cleaner ie, Seafoam or Techron. I prefer Techron but it doesn’t matter, just use one. Second, double check your work, very easy to mix plug wires. Also, while it’s idling, lightly tap on MAF. See if engine stumbles. Could be bad. Hope it all sorts itself out and you are on the road soon.
Really appreciate everyone’s help and patience. I’ll try not to ask dumb questions👍😎
Team Owner
Joined: Dec 2012
Posts: 30,427
Likes: 1,609
From: Outside the Quick Stop N.J.
You can find older OBD scanners pretty cheap on the used market, I believe there are even laptop programs that you can use. I have one that reads both OBD 1&2 that I bought from a member here for ~$150 IIRC.
Thread Starter
Intermediate
Joined: Feb 2022
Posts: 37
Likes: 5
From: Vancouver, WA
I would offer to come by and help, but that would be a helluva roundtrip.
You can find older OBD scanners pretty cheap on the used market, I believe there are even laptop programs that you can use. I have one that reads both OBD 1&2 that I bought from a member here for ~$150 IIRC.
You can find older OBD scanners pretty cheap on the used market, I believe there are even laptop programs that you can use. I have one that reads both OBD 1&2 that I bought from a member here for ~$150 IIRC.
Perhaps a laptop program in the future?
Team Owner
Joined: Dec 2012
Posts: 30,427
Likes: 1,609
From: Outside the Quick Stop N.J.
Patsgarage- checked your profile. That would be a ridiculous round trip👀….lol. Actually it turns out there is a forum member that’s local. He’s contacted me, has a scanner, and has offered to come by. I continue to be impressed by, and thankful for, the kindness of members of this forum. 😎
Perhaps a laptop program in the future?
Perhaps a laptop program in the future?
One day I am going to do a cross country road trip, but it is not in the cards just yet. I have a friend that does his own tuning via laptop, and others that swear by them. Personally I like the durability and ease of use of a handheld scanner. Good luck with your troubleshooting, keep us posted.
Team Owner
Joined: Dec 2012
Posts: 30,427
Likes: 1,609
From: Outside the Quick Stop N.J.
I just found the FS thread for the scanner I purchased, even cheaper than I thought.
https://www.corvetteforum.com/forums...scan-tool.html
https://www.corvetteforum.com/forums...scan-tool.html
Thread Starter
Intermediate
Joined: Feb 2022
Posts: 37
Likes: 5
From: Vancouver, WA
I just found the FS thread for the scanner I purchased, even cheaper than I thought.
https://www.corvetteforum.com/forums...scan-tool.html
https://www.corvetteforum.com/forums...scan-tool.html
Pro
Joined: Jun 2009
Posts: 697
Likes: 30
From: Kansas City, Kansas
Another simple part that I would consider maintenance in your situation would be the distributor pickup coil. Install and resetting the distributor is a little more involved, but a worthwhile and satisfying project, along with setting base timing.
Team Owner
Joined: Dec 2012
Posts: 30,427
Likes: 1,609
From: Outside the Quick Stop N.J.
I have not used it on my C4 (89) yet, but on my 86 Fiero I have to go into "service mode" to read live data, which includes a disclaimer not to drive the car. It is still a vary helpful tool that I recommend any DIY mechanic have in their toolbox.