cleaned throttle body and MAF and now problems - I need help

Not sure what he used, he just told me he cleans MAF sensors and throttle bodies all the time. He is a chinese guy and he knows his imports. I trust him. I just don't think it's the MAF sensor though. I am getting frustrated now as i been without a vehicle for 3 days now. I don't have another car. The only thing that bothers me is i brought the FX to him driving good and after he finished he parked it outside and gave me the keys. I mean didn't he hear the misfiring and smell the fuel before he took it out of his shop.
 
This is why I like to do my own work. If you're confident enough, I would try to diagnose and fix it yourself. Coilpacks getting mixed up seems likely, if they truly are all sparking.
 
Not sure what he used, he just told me he cleans MAF sensors and throttle bodies all the time. He is a chinese guy and he knows his imports. I trust him. I just don't think it's the MAF sensor though. I am getting frustrated now as i been without a vehicle for 3 days now. I don't have another car. The only thing that bothers me is i brought the FX to him driving good and after he finished he parked it outside and gave me the keys. I mean didn't he hear the misfiring and smell the fuel before he took it out of his shop.

He should have notice the problem when he started the car after cleaning and he didn't even tell you about it tells me a lot about the guy now. Have to got a chance to try out the suggestions we have mention above? Since he give you the car as it is as if everything is fine, I wouldn't trust him to do anymore diagnostics.

---------- Post added at 11:46 AM ---------- Previous post was at 11:44 AM ----------

Try to take some picture of the coilpacks and the connector and post up.
 
Well he tried a new MAF sensor and i still get the problem. I wasn't charged for the MAF sensor. My battery dies when you leave the door open for two minutes, so i knowi need a battery. Could the battery cause this? One guy mentioned a bad battery can actually cause code p0300. Even though the car can start the battery may be too weak to rin the rest of the car, even though the altenator charges it. I am not at the shop right now. I told him what to check so we will see, i am calling him in 10 minutes

---------- Post added at 10:10 AM ---------- Previous post was at 10:06 AM ----------

what bothers me the most is when i got my FX back and started it, i noticed the service engine light came on. I immediately told him and his response was, it was on when you dropped it off. I said no it wasn't. I probably won't bring it back again, i can't stand people who can't accept responsibility for what they do. Any other suggestions. I hope the battery is the issue as i was about to buy a yellow top anyways

---------- Post added at 10:12 AM ---------- Previous post was at 10:10 AM ----------

He;s a good mechanic and nice guy. I just think a lot of mechanics won't admit when they screw up cause they don't want to have to pay
 
A dead battery won't cause the issues you're having. Once the car is running, the battery doesn't really matter since the alternator powers everything. If the battery is strong enough to start the car (which is the hardest thing it does), then it won't cause other issues. You can actually disconnect the battery while your car is running and the car will still run (don't actually do this).

Why don't you have your guy check for actual causes of a misfire like plugs and coilpacks. Batteries don't cause misfires. Have him pull your plugs; the one/ones covered in fuel will be where your misfires are coming from. Have him swap the coil packs from these to other cylinders that are not misfiring. If the new cylinders start misfiring, the coilpacks are your problem. if it remains the same cylinders that are running rich and misfiring, either your sparkplug is messed up, or he messed up the wiring somehow. A possibility but unlikely due to timing would be a bad injector. I've had one of those in the past and it results in misfires and loss of power since the cylinder is flooding.
 
The plugs are brand new, he even got more plugs to test in case i got defective ones and that didn't solve anything. My cousin is coming to pick me up and he's also a mechanic. So my cousin is a mechanic, his father in law is a mechanic and everyone is stumped.
 
The coilpacks connector wires are labeled with a number on them. Check them out to see they're properly according to the cylinders.
 
he saud he checked all the coils and the plugs. he checked the grounds as well. he's gatting his friends snap on scanner to see if it picks uo more codes. not sure what else we can try

---------- Post added at 02:02 PM ---------- Previous post was at 02:01 PM ----------

if this last attempt fails i will take it to the dealership
 
this is crazy reading this. obviously mechanic one way or another and very shitty he's not helping you out more on this. Makes me sick. His true character is showing.
 
How are a bunch of mechanics stumped? This isn't rocket science. It's very simple, your car is misfiring and running rich. You have a code for misfires, troubleshoot that first. You've already tried new plugs so it's not that. The next obvious place would be the coilpacks. Do not take his word for it, he has absolutely no idea what he is doing. Have someone else check it, or do it yourself. Check that all of the wires are plugged into the right coils, as Andy said they are numbered. If they are correct, then swap the coils. Pull your plugs and see which ones are misfiring, then swap coils. This entire process will take 30 minutes. If you take it to a dealer, they will pull the code, replace all of your coils because they can and charge you $1k. That will likely fix the problem, but I 2 old recommend checking yourself first since that is free.

For some reason your mechanic decided to just replace the MAF sensor even though you don't throw a code for that. He didn't charge you for it so he's not fraudulent, just incompetent. And then the battery was blamed? When trouble issues come up, always test the components that most directly impact the issue. For misfires, it's plugs, coils, ignition wires, maf, and injectors. Maybe one in a million chance your ECU got cooked resulting in misfire. What happens if you take your car to ttis mechanic if it overheats? Will he replace the rear suspension and then be confused as to why it didn't fix the problem?

he saud he checked all the coils and the plugs. he checked the grounds as well. he's gatting his friends snap on scanner to see if it picks uo more codes. not sure what else we can try

---------- Post added at 02:02 PM ---------- Previous post was at 02:01 PM ----------

if this last attempt fails i will take it to the dealership
 
There should be a white label just right after the grey connector with a number on it. The driver side is cylinder 2, 4, 6 from front of car to the firewall respectively. The passenger side is 1, 3, 5 front of car to firewall respectively

Here is a picture so you can see how easy it is to connect them in the wrong order.
DSC04098_S_zps96c4f501.jpg
 
So my mechanic thinks the bad battery might have messed up the computer and now i need to take it to the dealership for a computer flash or consult. He tried everything and he knows his imports really good. My o2 sensors are good, my catalyc is good, coils are good, grounds are good. So it will be off to the dealership on monday. It starts with no problems and idles good, it's just dumping in a lot of fuel and running rich
 
Ok...can he explain why a bad battery would mess up the ecu? Battery has nothing to do with ecu. You could unplug your battery for a year and the car would start fine when you got back. The ecu doesn't lose its base memory without power. You lose adaptations and stuff, but not the baseline. A voltage surge could mess up the ecu, but that's the alternator, not the battery. Our voltage regulators are in the alternator.

Sounds like you admitted to him the battery was bad and once he found that out, he's blaming that instead of investigating.

So earlier you said it didn't idle good and now it does. Did anything change? If it's dumping too much fuel, could be injector. Did he mess with those? They are pretty reliable and don't fail that often

And i know you swapped maf, but did you check the connector? If he damaged the connection there a new maf wouldn't fix it.
 
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I'm totally agree with shadow, dead battery will not "mess up" the ECU. Your mechanic is looking for a way to get himself of the hook, if you ask me.

---------- Post added at 04:27 PM ---------- Previous post was at 04:25 PM ----------

Shadow, I think we gave him enough suggestions and ideas for troubling it, but seems like he just wants to drop it off at the dealer. Oh well, let it be.
 
I am not mechanically inclined so i can't check myself. I have printed and showed him everything you guys have suggested actually. I know it's not the battery but i needed one anyways and he doesn't necessarily blame it on the battery, he has tried everything and even consulted with other mechanics. My cousin that i hang with is a mechanic and he can't figure out why either. It was never idling high, it was just idling rough i guess due to the misfiring. We checked everything with the MAF sensor and we know it's not the throttle body either as when he cleaned it he never opened up the butterfly or took it off. He hasn't charged me for anything but at the end of the day if the dealership says it's something he caused he will pay for it. We even took out the MAF and drove it and there was no change as well. You guy are a great help but we have tried what you suggested and some. He understands the pedal dance and all that as well. At this point i just want it fixed and if he caused the problem i will deal with him, trust me. Even some here suggested to go to the dealership if everything tried fails and thats where i am at now. My cousin has been a great mechanic and i trust him. It was just too cold lately and my cousin drives a tow truck so we took it to out import mechanic instead of doing it ourselves. It may sound like he's trying to deflect blame but we're just eliminating the possibilities. Can anyone explain why it's running so rich? Like i said i am not getting the same symptoms as most after cleaning there throttle bodies so i don't thin it has to do with MAF or throttle body
 
This may be totally of subject, but have u checked the gas? Did u fill up before the repair? The reason I ask is u mentioned being really cold, in case u haven't noticed but r wonderful gas is absolute crap. That being said, ethonol attracts water and you throw in some sub zero weather and you got yourself some issues! Bad gas allot of times will idle but miss when under load, it's a shot in the dark but I have racked my brain trying to figure out problems with cars,boats,bikes. To finally realize the culprit all along was crappy gas! Good luck
 
Based on how things have gone, I think your best bet is to just take it to the dealer. The mechanic seems like he can't fix the issue, and if you don't want to go through checking all the stuff yourself then you're kinda stuck with taking it to the dealer. It's too bad so much work was done, because it's harder to nail down where the problem might be. Anything from plugs, coils, correct plug pattern for the coils, TB, MAF, air filter.
 
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