Car trouble part II

[Pat The Fox]

Alright, so here's the situation:

I have a 2003 pontiac sunfire with a bad idle/run. At low rpm the car shakes and sounds like it is missing on at least one cylinder. I have replaced the plugs, so it is clearly not that (it is rarely the plug, but it was the cheapest and easiest fix to attempt).

I know this could be a wide variety of problems now, and just wondering if someone could quote me a low end to high-end cost of what it could take to get the car back in working order.

Also, if anyone has suggestions on how to further diagnose the problem I am all ears.

Thanks in advance.

[Jeeper]

This may sound like a no brainer, but I have seen it.  Did you check the air filter?   Maybe the plug wires?

[Pat The Fox]

Have checked the filter, looked decently clean.

There are no spark plug wires on this model of vehicle. The vehicle uses a coil pack.

[Duffy]

Too bad I'm not closer. I have an OBD2 engine analyzer. I usually only finds problem that cause your check engine light to come on. but it can check for other things.

My dad had this car and he had to fix the wiring harness, there was a recall where the pins in the main connecter burned out. i don't think this is your problem though. It could be a simple problem like the O2 sensor, or the map/maf sensor. It's hard to say without checking the car. would be costly to just start replacing parts in hopes or finding the problem. best bet would be to take it for a diagnosis. might cost less than $100 for that.  Good luck, i know i hate having car problems.

[Jimfoxyboy]

Where did you say you were located again? If your nearby, I could offer to look at it, for nothing better to do. Note me if you want.

[Pat The Fox]

I'm in Central Van. Mount Pleasant area.

I agree just randomly replacing things is not the best idea. The spark plugs were worn down and did need to be replaced anyway, but it didn't solve the issue.

The other problem is it is a ten year old car almost, so if a repair is pricey, it is better to sell since I think at the very best you can only get around $3k for the car. I'm mainly trying to see if I can figure out what is wrong so I can give accurate information on what it is and how much it will cost since so far to even look at the thing most shops want over $100, which is a lot to part with if you end up having to walk away from the fix.

[Jimfoxyboy]

Ok.. still in the Vancouver area. I could come by and take a look if you want. Its hard to tell what could be wrong with it just by having it explained. Just let me know when and where. (It get me out of the house for a bit at least) Unless if you want to just sell it off as a junk car.

[Neox]

When the idling trouble occurs, listen carefully and see if you can hear your fuel-pump (rear of the car) revving up and down.  My sunfire has a lot of trouble with stop-and-go traffic, and the fuel pump starts to labour at low RPMs when I've been stuck in that kind of situation for longer than 10 minutes.  The thing runs fine in all other scenarios, but I'm still planning on replacing my fuel pump soon.

New fuel pump is usually in the $200-$300 range

Also, check the fuel filter.  Make sure that isn't plugged up.  Fuel filters are cheap (under $40).

You could also have a bad injector.  Removing the injector assembly is a pain in the ass, but it could be worth checking the injector nozzles and making sure they're not all gunked-up.  Not sure how much an injector nozzle costs, but you can probably get away with cleaning it if it's dirty.

[Pat The Fox]

I live at the Main and Boradway area, though if it is easier, I can come to you with the vehicle. Could probably use the drive since the battery is low from sitting in the parking lot.

Also, I admittedly do not have very many tools here to work with, just a set of wrenches and a driver with a set of spark plug sockets. I didn't bring my toolbox with me when I moved to BC and have just been getting new tools as needed, so ideally if things need pulling apart for any reason I'll either have to buy or borrow tools.

I was going to try a power test on the injectors if I could figure out how to safely disconnect the power. Have to go peek back in at the engine to see what I can and cannot do.

I am a little leery about mucking with the fuel filter just because I don't have a catch basin or any jack stands to lift the car on to. It is an easy job from what I've read, but I do not have the equipment on hand.

[Jimfoxyboy]

I have quite a few tools myself. I suppose you could bring it here, but we don't have much of a smooth driveway. There is a lot down in front of the machine shop bottom of the hill from us we could probably use, when they are closed. Guess we just need to figure out a time. Hopefully the car doesn't die on your way out here.

I'd want to just look/listen to see what is going on first before deciding what to do next. Just note me if your still interested. I'll give you the address there and contact if you want.

[Neox]

I live at the Main and Boradway area, though if it is easier, I can come to you with the vehicle. Could probably use the drive since the battery is low from sitting in the parking lot.

Also, I admittedly do not have very many tools here to work with, just a set of wrenches and a driver with a set of spark plug sockets. I didn't bring my toolbox with me when I moved to BC and have just been getting new tools as needed, so ideally if things need pulling apart for any reason I'll either have to buy or borrow tools.

I was going to try a power test on the injectors if I could figure out how to safely disconnect the power. Have to go peek back in at the engine to see what I can and cannot do.

I am a little leery about mucking with the fuel filter just because I don't have a catch basin or any jack stands to lift the car on to. It is an easy job from what I've read, but I do not have the equipment on hand.

Great Canadian Oil Change will change your fuel filter for, like, $10.  If you can get your car there, consider it.  According to their website, they'll also clean and flush your injectors.  Not sure how much though.  For the most part, their services aren't that expensive.

[Pat The Fox]

The car is mobile and can drive relatively decently. It just gets a bit finnicky at idle, dropping in to the sub 500 range, but I can keep it alive by reving or switching it in the neutral to disengage the load. Though, rather not drive it too far just because running with a misfire is generally a bad thing.

[tokar]

if you don't already belong, i suggest you join the BCAA.  plus i suggest you use their auto diagnostic service.  it will tell you everything you need to know about your car and best thing is, they come to you.
as an ex tow truck operator, BCAA is cheap insurance.

[Phyr]

You keep driving your car in the condition it is in you may be doing more damage to it then good if there is something wrong. Your car is a sun fire almost 10 years old you be lucky to get $1000 in working condition

[Jimfoxyboy]

Its been a week, were you able to get anything done since?

For anyone else that was curious: we traced the issue down to one of the cylinders. It was the only one with the super clean spark plug. There is a chance that the fuel injector isn't firing off due to bad wiring. Which in itself isn't hard to replace. Only other thing I can think of is a valve issue, which would mean some serious work.