Hey all,
Hope I'm in the right section of forum. I have a KN Laser 1.8l automatic, which is same as the Protege AFAIK. I have an issue with my Laser that is literally driving me insane..
When I first drive the car when cold it runs like a dream, but when the temp gets to normal operating temp, that's when it starts to hesitate and sound like it's running on 3 cylinders.
It will do this when there is very little inlet manifold pressure it seems, ie when cruising at say 70 and I just lightly put my foot on the accelerator it will jerk and cough, OR if I am at a roundabout standing still and I stomp on the throttle, it will go bababababa and then clear itself out and drive normal.
So far I have changed the following:
Plugs
Leads
Coil packs (2 of)
MAF sensor
Bosch fuel pump
Fuel filter
Throttle body to air intake pipe a couple of years ago
I have checked over all vacuum lines, brake booster lines, throttle body piping. I have checked under the car, I have checked for air leaks with a funnel/pipe. There is a very slight hiss from around the throttle body area but I can't pin point it with the funnel/pipe, it might even be a normal noise? Possible intake manifold gasket?
The funny thing is, is if I remove the temp sensor plug, it runs perfect even when warm, with no hesitation whatsoever. So hopefully this bit of info can help in fixing the issue?
I am almost at the point of giving up. It's disappointing throwing parts at it just to have it run like crap again. It actually ran worse with the new MAF sensor. But I don't want to keep buying the same new parts in chance that I got a dud.
I thought of injectors but why would it run beautiful with temp sensor unplugged?
Has anyone got any ideas? Please help as this is killing me
Thanks
Edit: The idle is fine too, it's only when I accelerate.
Hope I'm in the right section of forum. I have a KN Laser 1.8l automatic, which is same as the Protege AFAIK. I have an issue with my Laser that is literally driving me insane..
When I first drive the car when cold it runs like a dream, but when the temp gets to normal operating temp, that's when it starts to hesitate and sound like it's running on 3 cylinders.
It will do this when there is very little inlet manifold pressure it seems, ie when cruising at say 70 and I just lightly put my foot on the accelerator it will jerk and cough, OR if I am at a roundabout standing still and I stomp on the throttle, it will go bababababa and then clear itself out and drive normal.
So far I have changed the following:
Plugs
Leads
Coil packs (2 of)
MAF sensor
Bosch fuel pump
Fuel filter
Throttle body to air intake pipe a couple of years ago
I have checked over all vacuum lines, brake booster lines, throttle body piping. I have checked under the car, I have checked for air leaks with a funnel/pipe. There is a very slight hiss from around the throttle body area but I can't pin point it with the funnel/pipe, it might even be a normal noise? Possible intake manifold gasket?
The funny thing is, is if I remove the temp sensor plug, it runs perfect even when warm, with no hesitation whatsoever. So hopefully this bit of info can help in fixing the issue?
I am almost at the point of giving up. It's disappointing throwing parts at it just to have it run like crap again. It actually ran worse with the new MAF sensor. But I don't want to keep buying the same new parts in chance that I got a dud.
I thought of injectors but why would it run beautiful with temp sensor unplugged?
Has anyone got any ideas? Please help as this is killing me
Thanks
Edit: The idle is fine too, it's only when I accelerate.
Last edited: