Limp mode?
Thread Starter
1st Gear
Joined: Jan 2024
Posts: 1
Likes: 0
Limp mode?
Hello everyone,
my granpa gave me a 86 corvette if I could get it running, it sat for 10 years, I cleaned the tank, new sending unit, pump, fuel filter, oil change, battery, distributor cap, rotor, spark wires, and spark plugs.
it idles rough but my main issue is when I get about a 1/4 mile down the highway not sure if it goes into limp mode but it looses power and if you don’t let it idle it will bog down and turn off. After letting it sit for a couple minutes I can drive it another 1/4 mile, anything I should look into?
thanks!
my granpa gave me a 86 corvette if I could get it running, it sat for 10 years, I cleaned the tank, new sending unit, pump, fuel filter, oil change, battery, distributor cap, rotor, spark wires, and spark plugs.
it idles rough but my main issue is when I get about a 1/4 mile down the highway not sure if it goes into limp mode but it looses power and if you don’t let it idle it will bog down and turn off. After letting it sit for a couple minutes I can drive it another 1/4 mile, anything I should look into?
thanks!
Team Owner
Joined: Jul 2006
Posts: 22,800
Likes: 485
From: Douglas County WI
Sounds like when it hits a certain temp it loses power and letting it sit it cools down and is good to go until it hits that temp again. I have no idea what it could be but I'd start with the thermostat and/ or temp sending unit. Or possibly the engine control module ( if there is one. Not too familiar with c4s) Good luck.
Safety Car
Joined: Mar 2017
Posts: 4,202
Likes: 1,323
From: LeClaire Iowa
Your FIRST step is to check for codes. There are a lot of posts on here about how to check for codes with a paper clip. I find it way easier to use a 10 buck code reader. Dan
edit: Whatever is causing the car to go into limp mode I guarantee you HAS set a code.
edit: Whatever is causing the car to go into limp mode I guarantee you HAS set a code.
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
Wondering if the O2 sensors are bad. Once warmed up they give feedback to computer to adjust fuel mixture. Also electrical parts from that era can fail with heat. It would be interesting to know if good spark is going to plugs when that happens. Old guys pull an easy plug wire, put a screw driver in it and hold next to engine while someone cranks to look at spark. There are tools for that, but when I was taught I was also poor lol.
