replacing the fuel filter...

[ithinkshescrazie]

I have a 1990 Lemans & I'm trying to replace the fuel filter..can anyone tell me where it is and the best way to go about changing it? please! & also it had been randomly cutting off every now and then but now it shuts off after about 5 seconds of being at a red light/stop sign/etc. basically when it idles for more than 5 or 10 seconds.. if you give it gas it will stay running but sounds rough.. any ideas on that would be greatly appreciated.. it's got new spark plugs/wires and all that jazz a brand new battery and the alternator checks out fine..There's no trouble cranking it, just doesn't want to stay running.

[Jim Adams]

The fuel filter should be against the fire wall next to the brake booster down a little lower ,,if not then under the car on the frame rail on drivers side but should be at first location,,Check for trouble codes auto zone checks for free!! good luck!

[ithinkshescrazie]

Thanks! I'll be trying that.. but I have no idea what trouble codes are... can you fill me in??

[Doubleshot]

the ecm (computer) controls a number of sensors on the engine that controls fuel mixture/delivery and timing to keep with in the emissions specs set by the govt. If any of these sensors either fail or go out of range/specs the ecm stores that info as a trouble code. You can see these on early (obd1) systems by shorting the two connectors on the upper right of the LDL. A paper clip will work. After shorting the connector, turn the key on, not started (key on engine off) and the check engine light will flash the code. a code twelve would be flash......flash flash. it will repeat three times and go on to the next. You can find these older codes easily on the net. Remember however, the code does not mean the sensor is bad. A dirty air cleaner will tell you there is a rich condition on the o2 sensor. Check the injectors for proper resistance (in the manual) as they will fail and not give a code.
A lot of troubleshooting before you spend money on these older vehicles. Look at the mechanical and make sure all is well, vacuum lines, filters, tuneup etc before blaming the electronics....Good luck and stay with it, you will figure it out.

[Jim Adams]

to further explain Doubleshots post,,the service engine soon light will flash a code 12 three times this means beginning of message so 1 flash then two flashes ,,it will do this 3 times and then start with the trouble codes,,when it gets to the end of the trouble codes or has no codes then 12 will flash again three times,,dont want you to get confussed and think code 12 is a trouble code it only is telling you system is working and beginning of message and end of message.

[ithinkshescrazie]

Thank you for all the help!! We got the fuel filter replaced & took the car to auto zone and got the trouble codes checked. They said there were no problems so I guess that's a good thing. But it's still not running right. After we got the fuel filter on it stayed running for about 10 minutes but when we got in it to ride around and see how it was gonna run it died when it was put in reverse. It seems like the fuel filter might have helped the problem some, b/c at times it will idle for a little while before it dies. If we stop at a red light and put it in neutral and give it a little gas it wont die but if you dont it most like will. but almost every time its put in reverse it dies & it continues to die two or three times before you actually get finished backing out. So if anyone has anymore ideas we'd appreciate those too!

[ctesla]

in neutral it stays idling?
sounds like clutch master/slave might be giving, and so the disc is giving just enough drag to allow idle to falter.
is the idle rough if just setting in neutral?

[Jim Adams]

Of it is not coding then you have no sensor problems but you may hav tune up problems or vaccuum leak issues,,,Try giving it a tune up ,,plugs wires cap and rotor if it has one, then spray some carb cleaner around vacuum routing and intake manifold and look for a raise or a smooth in idle,,if you find an area examine for the obvious things ,,broken vaccuum lines,loose vaccuum lines,,if you find a spot in the intake switch to water spray and go to the area and see if it faulters when you spray it there,,,sometimes carb cleaner will find its way in when other liqiuds cant and the water may show there is infact no leak but if it shows a leak then make your repairs and try it out,,,did you disconnect your battery and hit the brakes 3 times to clear out your computer?

[ithinkshescrazie]

Originally Posted by ctesla

in neutral it stays idling?
sounds like clutch master/slave might be giving, and so the disc is giving just enough drag to allow idle to falter.
is the idle rough if just setting in neutral?

Is that expensive??? & the idling doesn't really change much if any. I would say if anything it might actually be a little smoother in neutral.

[ithinkshescrazie]

Originally Posted by Jim Adams

Of it is not coding then you have no sensor problems but you may hav tune up problems or vaccuum leak issues,,,Try giving it a tune up ,,plugs wires cap and rotor if it has one, then spray some carb cleaner around vacuum routing and intake manifold and look for a raise or a smooth in idle,,if you find an area examine for the obvious things ,,broken vaccuum lines,loose vaccuum lines,,if you find a spot in the intake switch to water spray and go to the area and see if it faulters when you spray it there,,,sometimes carb cleaner will find its way in when other liqiuds cant and the water may show there is infact no leak but if it shows a leak then make your repairs and try it out,,,did you disconnect your battery and hit the brakes 3 times to clear out your computer?

We have changed the plugs and wires and cap and all that, it has actually been acting worse since we did that, but a little better after we changed the fuel filter. someone else suggested it may be a vacuum line.. we havent tried that yet..We found a few lines that were totally not connected & connected them back up but were not sure what they go to. we didn't disconnect the battery and cleear the computer.. unless they did it when it was taken to auto zone to check the codes. I was there then. I'll have to ask if they did that.

[ctesla]

sounds like if it got worse after tune-up, then better after fuel filter,
probably needs computer cleared, then check for the vacuum leaks as Jim suggested, but also check your timing, as your LeMans is an import, so unlike most Pontiacs after 87/88, you still have a distributor.

[ithinkshescrazie]

someone else had suggested that it might be the timing the problem there is my boyfriend (his car) doesn't know anything about that & if it isnt obvious enough i dont know much about anything. Can you give me an idea of how i would go about checking to see if the timing is off??