YACT: troubleshooting help

[godmare]

I've an '88 nissan pulsar, 1.6i four cylinder TBI, auto trans.
I'm having a problem with stalling, could use some other opinions...
With the car in gear nad driving, when the engine revs lower, often times the car completely stalls out- hitting the gas has no effect- like it's choking.
It will run fine in park or neutral no problem, the engine will rev up to 3 and 4k without issue, unless the a/c is on, then it will stall out when the revs lower.
It runs much better cold, stalling starts once it heats up.
This car originally came from a mechanic that held it for payment, and the original owner abandoned it- according to him the catalytic converter was bad, and it has not been replaced yet.
This seems to me like it may be just a clogged catalytic converter, and replacing it would solve the stal problem.
What say you, atot?

 

[WannaFly]

Ohoh i know i know!
Sounds like you need to take the radiator cap off and put a new car under it.

 

[Zenmervolt]

I agree that it could well be the catalytic converter. Without an extermal load, the engine has just enough power to force the exaust out past the restriction in the catalytic converter. With extra load, it can't make enough power to overcome the load and the restriction.

ZV

 

[IshmaelLeaver]

Unhook the cat and see if it fixes it. If so, get a new cat.

 

[Zenmervolt]

Originally posted by: IshmaelLeaver
Unhook the cat and see if it fixes it. If so, get a new cat.

Not always possible. Sometimes you have to cut the cat out and weld the new one in.

ZV

 

[godmare]

Cool, thanks ZV
I should be able to replace it this week.... I suppose I'll post an update.

 

[Quixfire]

Originally posted by: godmare
Cool, thanks ZV
I should be able to replace it this week.... I suppose I'll post an update.

Do you have an update yet?

 

I've an '88 nissan pulsar, 1.6i four cylinder TBI, auto trans.
I'm having a problem with stalling, could use some other opinions...
With the car in gear nad driving, when the engine revs lower, often times the car completely stalls out- hitting the gas has no effect- like it's choking.
It will run fine in park or neutral no problem, the engine will rev up to 3 and 4k without issue, unless the a/c is on, then it will stall out when the revs lower.
It runs much better cold, stalling starts once it heats up.
This car originally came from a mechanic that held it for payment, and the original owner abandoned it- according to him the catalytic converter was bad, and it has not been replaced yet.
This seems to me like it may be just a clogged catalytic converter, and replacing it would solve the stal problem.
What say you, atot?

Pull the trouble codes first.

 

[godmare]

Originally posted by: Quixfire

Originally posted by: godmare
Cool, thanks ZV
I should be able to replace it this week.... I suppose I'll post an update.

Do you have an update yet?

Not yet, I'm in the midst. I work all the weekend, probably it'll draw into next week.

Originally posted by: Roger

I've an '88 nissan pulsar, 1.6i four cylinder TBI, auto trans.
I'm having a problem with stalling, could use some other opinions...
With the car in gear nad driving, when the engine revs lower, often times the car completely stalls out- hitting the gas has no effect- like it's choking.
It will run fine in park or neutral no problem, the engine will rev up to 3 and 4k without issue, unless the a/c is on, then it will stall out when the revs lower.
It runs much better cold, stalling starts once it heats up.
This car originally came from a mechanic that held it for payment, and the original owner abandoned it- according to him the catalytic converter was bad, and it has not been replaced yet.
This seems to me like it may be just a clogged catalytic converter, and replacing it would solve the stal problem.
What say you, atot?

Pull the trouble codes first.

iirc, the codes were not conclusive.. they were checked some time ago.
I'll double check at the next opportunity, though... I should do that anyway.
Thanks

 

Remove the AIS motor assembly (Automatic Idle Speed) and clean the carbon from the pintle with carb clean, reinstall, disconnect negative battery terminal (Remove the key from the ignition), wait 15 minutes and reinstall negative cable.
Start vehicle and drive normally for 15 minutes or until it is fully warmed up.