Engine Runs Very Rough

[Tywais]

This just started yesterday when I started the car to go home. It started normally but very rough idle and under load very little power, thought I wasn't going to get home. Similar to plugs not firing. It is a 93 Nissan Bluebird 2 liter turbocharged. Obviously several things could be the cause, bad plugs, vacuum, dirty injectors, etc but the problem just started suddenly. After driving it for several kilometers the problem pretty much goes away. Started it again this morning and the same symptoms until the engine warms up and it is normal again.

The question I have is that the last 2-3 weeks I have not been able to find 95 benzine and twice put in 95 gasohol as an emergency fill up (only 1000 baht each time). I needed to fill up again last night and decided to put 91 benzene in (this was after the symptoms started). Seems to be no knocking due to pre-detonation and was wondering if the gasohol could be at fault, possibly water in it though the problem disappears after warmup.

Planning on taking it to a shop, but once it is warm the symptoms disappear and not sure how to explain the issue.

[dotcom]

Sounds like a problem with the choke.

[Tywais]

Sounds like a problem with the choke.

It's turbo charged fuel injected so suspect there is no choke.

[bino]

I'd imagine that your car has electronic fuel injection as opposed to a carburetor / choke...

If so, you might want to get a Nissan dealer to run a diagnostic test on your electronic engine management and sensors. Your problems sound symptomatic of the O2 (oxygen in exhaust) sensor and / or MAP (intake manifold air pressure) sensor.

The O2 sensor in particular becuse it is measuring the exhaust gas temperature and amount of oxygen (hence unburned fuel)while the car is warming up to "normal" tempeerature- in the hundreds of degrees, and feeding this info to the computer to adjust the fuel injection accordingly.

If it is faulty, the engine will be running too "rich" when cold because the computer is not getting accurate temperature information, but OK once it reaches normal temperatures / parameters for the system.

[thaicbr]

tywais your engine can run 91 with no problems but was never designed for an ethanol mix so this is the problem fill up with regular 91 or 95 only. also if the car was left standing in the sun for a few days the ethonal catches the water from evaporation. the stuff makes my cbr250 motorbike run like a dog at low revs.

[Tywais]

tywais your engine can run 91 with no problems but was never designed for an ethanol mix so this is the problem fill up with regular 91 or 95 only. also if the car was left standing in the sun for a few days the ethonal catches the water from evaporation. the stuff makes my cbr250 motorbike run like a dog at low revs.

A friend said the same thing about his motorbike when using gasohol. Very rough when cold but ok when warm. So far 91 doesn't seem to be a problem. Will be dropping it off at a shop tomorrow morning. Had to start the car and just let it idle for 6 or 7 minutes before it starts smoothing out again. Thanks.

[sunny747]

this is the exact problem i'm having with my 95 lancer. It takes lot of efforts to start the engine but one of my thai friend increased the race and now it is somewhat ok but consumes lot of gas.

nevertheless, the car is smooth while the engine is warm. I took to the repair shop but by the time i get there, the engine is hot and it was a hel_l explaining to them. so i gave up.

[mijan24]

I'd imagine that your car has electronic fuel injection as opposed to a carburetor / choke...

If so, you might want to get a Nissan dealer to run a diagnostic test on your electronic engine management and sensors. Your problems sound symptomatic of the O2 (oxygen in exhaust) sensor and / or MAP (intake manifold air pressure) sensor.

The O2 sensor in particular becuse it is measuring the exhaust gas temperature and amount of oxygen (hence unburned fuel)while the car is warming up to "normal" tempeerature- in the hundreds of degrees, and feeding this info to the computer to adjust the fuel injection accordingly.

If it is faulty, the engine will be running too "rich" when cold because the computer is not getting accurate temperature information, but OK once it reaches normal temperatures / parameters for the system.

Ceretainly could be the gasahol but I think Bino is more on the trail of your problem EGR/ERG depends where you originate certainly rough idle low power on acceleration warm can be OK.

[Tywais]

Ceretainly could be the gasahol but I think Bino is more on the trail of your problem EGR/ERG depends where you originate certainly rough idle low power on acceleration warm can be OK.

Odd thing now is after switching from gasohol and using 91 for two days the problem has disappeared. The day I was planning on dropping it off at a shop the problem cleared. Now no symptoms to tell the shop what to look for. Starting to look for a new car anyway after putting it off for a couple of years. Thanks for all the feedback.

[mijan24]

Ceretainly could be the gasahol but I think Bino is more on the trail of your problem EGR/ERG depends where you originate certainly rough idle low power on acceleration warm can be OK.

Odd thing now is after switching from gasohol and using 91 for two days the problem has disappeared. The day I was planning on dropping it off at a shop the problem cleared. Now no symptoms to tell the shop what to look for. Starting to look for a new car anyway after putting it off for a couple of years. Thanks for all the feedback.

Tywais Happy Motoring

Edited July 13, 2008 by mijan24