Corvette sluggish on acceleration......
Thread Starter
Instructor
Joined: May 1999
Posts: 215
Likes: 0
From: Harlingen TX
Corvette sluggish on acceleration......
I hadnt driven the vette in awhile because ive been using the truck for skewl so i took it out and as i was driving something didnt feel right. when i came to a stop she started accelerate and decelerate on her own. i pulled in to a car wash and she shut right off. She started right back up again and seemed to be idling normal, but when i got back on the road she was very sluggish. i almost made it home before she started to accel and decel again. it turned off again. i finally made it home.
a few weeks back i went in and replaced the wires , cap, fuel filter, and rotor and it was running fine til that day. today i went in and replaced the plugs, but she was still very sluggish on accel.
some had said one of the sensors is bad, how can i know for sure?
--sal-
a few weeks back i went in and replaced the wires , cap, fuel filter, and rotor and it was running fine til that day. today i went in and replaced the plugs, but she was still very sluggish on accel.
some had said one of the sensors is bad, how can i know for sure?
--sal-
Le Mans Master
Joined: Oct 2000
Posts: 6,362
Likes: 30
From: Oak Harbor WA
Re: Corvette sluggish on acceleration...... (merrick)
How long has it been sitting?? You might have gotten some water in the gas tank and that is what is doing it. Any DTC's set by chance?? Maybe the IAC is sticking but I'm not so sure. Others may help out here. :seeya
Advanced
Joined: Sep 2001
Posts: 54
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From: fairfax va
Re: Corvette sluggish on acceleration...... (Mav)
You need to scan the codes. Here's a page that will help. http://www.thirdgen.org/faq/thirdgen.shtml#misc
You can also take it to a mechanic and they usually charge $60 to do this, but for that you could almost buy your own scan tool.
My guess is it's the TPS or the IAC. My sister's Saab had the same problem. It would rev all by itself sitting at a stop.
http://www.thirdgen.org/newdesign/tech/tpimod2.shtml
You can also take it to a mechanic and they usually charge $60 to do this, but for that you could almost buy your own scan tool.
My guess is it's the TPS or the IAC. My sister's Saab had the same problem. It would rev all by itself sitting at a stop.
http://www.thirdgen.org/newdesign/tech/tpimod2.shtml
Thread Starter
Instructor
Joined: May 1999
Posts: 215
Likes: 0
From: Harlingen TX
Re: Corvette sluggish on acceleration......
Thanks for the tips guys, the fuel filter is about 9 months old.
the plug wires dont seem to be in danger, but the car was parked for about two months, and the weather has been crappy, i would hate to have gotten watter in there.
ill check out the computer codes to see if i can pin point the sensor. the check engine light is not on though. although, it did come on during that episode.
thanks
--sal-
the plug wires dont seem to be in danger, but the car was parked for about two months, and the weather has been crappy, i would hate to have gotten watter in there.
ill check out the computer codes to see if i can pin point the sensor. the check engine light is not on though. although, it did come on during that episode.
thanks
--sal-
Thread Starter
Instructor
Joined: May 1999
Posts: 215
Likes: 0
From: Harlingen TX
Re: Corvette sluggish on acceleration......
the check engine light gave me codes 22, 34, and 45.
which are.
22. Low voltage at throttle position sensor OR
Fuel cutoff relay circuit open or shorted to ground
34. Low voltage (high vacuum) at mass air flow sensor (or MAP sensor)
45. Oxygen sensor rich
i guess im going to have to find me a mechanic to take over from here, because i cant find any info on how to fix this myself.
thanks
--sal-
which are.
22. Low voltage at throttle position sensor OR
Fuel cutoff relay circuit open or shorted to ground
34. Low voltage (high vacuum) at mass air flow sensor (or MAP sensor)
45. Oxygen sensor rich
i guess im going to have to find me a mechanic to take over from here, because i cant find any info on how to fix this myself.
thanks
--sal-
Team Owner
Joined: Sep 2001
Posts: 62,180
Likes: 1,740
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Corvette sluggish on acceleration...... (Mav)
34 you should be able to fix yourself easy. There are two relays behind the battery that you need to change first. IF the code 34 comes back, then you need to change the MAF sensor itself. It is the thing between the air filter housing and the TB with wires coming out of it. A new MAF will cost about $220-250 and the two relays will cost $20 or so.
your O2 sensor will prolly need replacing if fixing the TPS doesnt solve that problem. these could all be related so fix the 34 first
your O2 sensor will prolly need replacing if fixing the TPS doesnt solve that problem. these could all be related so fix the 34 first
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Burning Brakes
Joined: Sep 2001
Posts: 1,162
Likes: 76
From: Sumter, SC
Re: Corvette sluggish on acceleration...... (vader86)
It's possible that when the car shut off or was stubling that caused the code 34. I would replace the 02 sensor first because that's the easiest. Then reset the codes and try again. If it does it again, check the codes right then.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: Corvette sluggish on acceleration......
Think you may have a common issue between the code 34 and code 22. Both indicate very, very low voltages (not possible) from the TPS sensor and the MAP sensor. Now I don't have a 90 (or speed density) manual but I'll bet the TPS and MAP must share a common wire or harness. I would trace these wires and check the (probably gray) 5V reference voltage at both sensors.
Look for mouse mischief!
This would also explain the rich code, which I wouldn't worry about and will probably clear when the other problem is found.
Good Luck,
Pete
Look for mouse mischief!
This would also explain the rich code, which I wouldn't worry about and will probably clear when the other problem is found.
Good Luck,
Pete
