1989 L98 Issues
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1989 L98 Issues
All,
Got my 89 out of storage for the year on Friday. Filled it up with non-ethanol and took it on about a 20 mile drive until the car started to seem down on power and started running rough. I started it back up yesterday just to see if it was maybe an intermittent problem that would go away, but no, it is still idling rough and running crappy. No idiot lights on either, any suggestions? BTW, the injectors are still stock.
Thanks (This should be moved to the tech area, sorry)
Got my 89 out of storage for the year on Friday. Filled it up with non-ethanol and took it on about a 20 mile drive until the car started to seem down on power and started running rough. I started it back up yesterday just to see if it was maybe an intermittent problem that would go away, but no, it is still idling rough and running crappy. No idiot lights on either, any suggestions? BTW, the injectors are still stock.
Thanks (This should be moved to the tech area, sorry)
Last edited by R254; Apr 24, 2018 at 10:56 AM.
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I could also be the O2 sensor. Mine didn't throw a code until it was really, really, really bad. But it had started running like crap....especially when warmed up.
A good indicator of this is: "normal" operation during warm-up...then degrading performance as closed-loop (computer monitored) operation starts. Depending on how hot it is/was before start-up, closed-loop engages after 5, 3, or 1 min (cold/warm/hot). O2 sensor isn't monitored until closed loop.
A good indicator of this is: "normal" operation during warm-up...then degrading performance as closed-loop (computer monitored) operation starts. Depending on how hot it is/was before start-up, closed-loop engages after 5, 3, or 1 min (cold/warm/hot). O2 sensor isn't monitored until closed loop.
Last edited by GREGGPENN; Apr 25, 2018 at 11:51 AM.
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I could also be the O2 sensor. Mine didn't throw a code until it was really, really, really bad. But it had started running like crap....especially when warmed up.
A good indicator of this is: "normal" operation during warm-up...then degrading performance as closed-loop (computer monitored) operation starts. Depending on how hot it is/was before start-up, closed-loop engages after 5, 3, or 1 min (cold/warm/hot). O2 sensor isn't monitored until closed loop.
A good indicator of this is: "normal" operation during warm-up...then degrading performance as closed-loop (computer monitored) operation starts. Depending on how hot it is/was before start-up, closed-loop engages after 5, 3, or 1 min (cold/warm/hot). O2 sensor isn't monitored until closed loop.
Last edited by R254; Apr 25, 2018 at 11:59 AM.
Drifting
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Finalist 2020 C4 of the Year - Unmodified
fuel
spark
air
SES code
Service Engine Soon code is definitely the first thing to check, should see at least code 12.
Last edited by kael; Apr 26, 2018 at 01:11 PM.
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That is classic O2 sensor behavior. Replace it first. There's only one and they're cheap. Go from there.
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With those, you don't even have to worry about ethanol or non-ethanol. It's a PITA to have to limit yourself to 2 or 3 gas stations and plan your drive around them.
Last edited by aklim; Apr 27, 2018 at 12:57 PM.
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Do it again. This time, when it goes rough, pull the MAF wire and see if that helps. Wouldn't hurt to change the O2 if it has been a while. If you need injectors, and you probably will sooner or later, FIC will help.
With those, you don't even have to worry about ethanol or non-ethanol. It's a PITA to have to limit yourself to 2 or 3 gas stations and plan your drive around them.
With those, you don't even have to worry about ethanol or non-ethanol. It's a PITA to have to limit yourself to 2 or 3 gas stations and plan your drive around them.
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I am talking to a local mechanic right now to see if he can take a look and get it on his lift to change the O2 sensor. I had an 89 GTA that had the injectors go bad and it smelled like fuel and basically would not run. This runs, just not well.
I need to find an 89 FSM and start doing everything myself.....but a lift makes life a lot easier.
Last edited by R254; May 1, 2018 at 11:00 AM.
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Yep.
I am talking to a local mechanic right now to see if he can take a look and get it on his lift to change the O2 sensor. I had an 89 GTA that had the injectors go bad and it smelled like fuel and basically would not run. This runs, just not well.
I need to find an 89 FSM and start doing everything myself.....but a lift makes life a lot easier.
I am talking to a local mechanic right now to see if he can take a look and get it on his lift to change the O2 sensor. I had an 89 GTA that had the injectors go bad and it smelled like fuel and basically would not run. This runs, just not well.
I need to find an 89 FSM and start doing everything myself.....but a lift makes life a lot easier.
As to the injectors, if they are Multecs I'd do it so that I can gas up anywhere without having to hunt down the few and far away stations that sell pure gas. Reman is about $200. Go ohm it and if you have any deviation, change it all. If not, put I down as a to do as soon as possible item
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If you want to, it is easy to change the O2 sensor. If you don't know when it was last changed, just change it since it is probably due.
As to the injectors, if they are Multecs I'd do it so that I can gas up anywhere without having to hunt down the few and far away stations that sell pure gas. Reman is about $200. Go ohm it and if you have any deviation, change it all. If not, put I down as a to do as soon as possible item
As to the injectors, if they are Multecs I'd do it so that I can gas up anywhere without having to hunt down the few and far away stations that sell pure gas. Reman is about $200. Go ohm it and if you have any deviation, change it all. If not, put I down as a to do as soon as possible item
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4 cylinders on the left side. All dump into the manifold and it narrows down to a single pipe. A little after that pipe is the sensor. Go get a Bosch sensor from Autozone or something.
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Great, I will do it right after work. When replacing this sensor, do you put any sealant like ultra copper on the threads of the sensor?
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Yup....it's a bit forward/left of the oil filter...off the DS exhaust downpipe. Easy to change...like a spark plug. It screws in and plugs in with a single wire. Can't remember if ears broke off the plastic...or it's just possible to pop open... (dang plastic) Anyway, I just use a small zip-tie to keep the connector from coming unplugged.
I use a dab of copper anti-seize to make it more easily removable.
Buy the new one first. That will make it easy to find/identify.
I use a dab of copper anti-seize to make it more easily removable.
Buy the new one first. That will make it easy to find/identify.
Last edited by GREGGPENN; May 1, 2018 at 01:45 PM.
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Do it again. This time, when it goes rough, pull the MAF wire and see if that helps. Wouldn't hurt to change the O2 if it has been a while. If you need injectors, and you probably will sooner or later, FIC will help.
With those, you don't even have to worry about ethanol or non-ethanol. It's a PITA to have to limit yourself to 2 or 3 gas stations and plan your drive around them.
With those, you don't even have to worry about ethanol or non-ethanol. It's a PITA to have to limit yourself to 2 or 3 gas stations and plan your drive around them.