Hesitation
05-09-2003, 10:37 AM
#1
Melting Slicks
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Hesitation
My 1994 tends to hesitate when the engine is hot (after about 30 minutes). When the engine is cold the car has so much power that I could easily do the 1st gear to 4th gear shift but when the engine is hot the car bogs down. When i try to shift 1st to 4th gear the car will jerk a couple of times.
When the car is hot I can not do a 2nd gear rolling stop it also bogs down.
What do you guys think it is? Opti-crap?
[Modified by CanadaVette, 3:38 PM 5/9/2003]
When the car is hot I can not do a 2nd gear rolling stop it also bogs down.
What do you guys think it is? Opti-crap?
[Modified by CanadaVette, 3:38 PM 5/9/2003]
05-09-2003, 01:45 PM
#3
Team Owner
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Re: Hesitation (CanadaVette)
It could be an ignition problem but I don't know much about the opti.
Try cleaning the TB bore and plates and maybe the IAC of carbon buildup.
It may just be that the motor is lugging due to drop in torque with elevated operating temps. A low temp stat & fan switch will help with this issue.
Try cleaning the TB bore and plates and maybe the IAC of carbon buildup.
It may just be that the motor is lugging due to drop in torque with elevated operating temps. A low temp stat & fan switch will help with this issue.
05-09-2003, 02:16 PM
#4
Burning Brakes
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Re: Hesitation (CanadaVette)
Sounds like the way mine acted when the opti went bad.
Ran good as long as the rpm were up, but as soon as I put a load on the engine at low rpm, it would kind of skip/jerk real hard.
[Modified by 92corvette, 1:21 PM 5/9/2003]
Ran good as long as the rpm were up, but as soon as I put a load on the engine at low rpm, it would kind of skip/jerk real hard.
[Modified by 92corvette, 1:21 PM 5/9/2003]
05-09-2003, 02:17 PM
#5
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Re: Hesitation (CanadaVette)
Mine does the same thing, and I only know what didn't fix it:
Opti
Water pump
Fuel filter
plugs
wires
IAC
Probably some other things I don't remember. My guess is that is is knock/temperature related since the symptoms largely went away with winter and are coming back now that temps are rising.
I will probably try a 160 thermostat and get the fans reprogrammed next.
Opti
Water pump
Fuel filter
plugs
wires
IAC
Probably some other things I don't remember. My guess is that is is knock/temperature related since the symptoms largely went away with winter and are coming back now that temps are rising.
I will probably try a 160 thermostat and get the fans reprogrammed next.
05-09-2003, 02:20 PM
#6
Burning Brakes
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Re: Hesitation (rcdk)
Mine does the same thing, and I only know what didn't fix it:
Opti
Water pump
Fuel filter
plugs
wires
IAC
Probably some other things I don't remember. My guess is that is is knock/temperature related since the symptoms largely went away with winter and are coming back now that temps are rising.
I will probably try a 160 thermostat and get the fans reprogrammed next.
Opti
Water pump
Fuel filter
plugs
wires
IAC
Probably some other things I don't remember. My guess is that is is knock/temperature related since the symptoms largely went away with winter and are coming back now that temps are rising.
I will probably try a 160 thermostat and get the fans reprogrammed next.
05-10-2003, 12:07 AM
#7
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Re: Hesitation (92corvette)
He didn't say that his problem went away in winter, just that it started after the car warmed up. My problem goes away in winter or on cooler days, and only exhibits itself after the car has warmed up.
Another possibility is O2 sensors, since they do have to heat up to put you in closed loop. But that shouldn't take very long, the engine temps should still be pretty cool then.
The GM dealer couldn't find my problem, but they may not have driven the car until it was good and hot.
Another possibility is O2 sensors, since they do have to heat up to put you in closed loop. But that shouldn't take very long, the engine temps should still be pretty cool then.
The GM dealer couldn't find my problem, but they may not have driven the car until it was good and hot.
05-10-2003, 09:37 AM
#8
Melting Slicks
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Re: Hesitation (92corvette)
Sounds like the way mine acted when the opti went bad.
Ran good as long as the rpm were up, but as soon as I put a load on the engine at low rpm, it would kind of skip/jerk real hard.
[Modified by 92corvette, 1:21 PM 5/9/2003]
Ran good as long as the rpm were up, but as soon as I put a load on the engine at low rpm, it would kind of skip/jerk real hard.
[Modified by 92corvette, 1:21 PM 5/9/2003]
Mine only does it after it is hot (Hot engine).
I will check the engine temp next time it does that.