318ti cylinder 3 misfire

[aayp170]

Because my 1998 318ti cylinder 3 is misfiring, I changed the plugs. It helped a bit, but not perfect yet. Do I replace plug wire #3 (and who sells that aftermarket??) or do I go to a new coil pack?
Any help is appreciated.

[ChItalian1027]

i would change the plug wire #3.

do you have an aftermarket wire??

[cooljess76]

Why not change all of your wires? I mean it's pretty ghetto to change just one if you ask me. I've heard a few stories about people checking their spark plugs to find out that they don't all match. It's no wonder why these people's cars don't run properly.

[Mad Machine]

for all the aggravation of replaceing 1 wire. do all four. It is a painhow they wrap around the head. Plus they are bundled together in a loom

[scabzzzz]

coil pack? how do you know if cylinder 3 is misfiring? unless your wires are busted up and have some serious fouling on the spark plug, i would check compression for that cylinder. thats probably your problem. you didnt include any information on how you got to that point yo!

[aayp170]

Thanks for the input. I like the ideas given me by respondents and I thank you for your input. NOT taking a car to a dealership and solving problems with friends is the heart and soul of the 'hot rod' and hobbyist community.

(However, the slur, "it's pretty ghetto to change just one (wire) if you ask me," from 'cooljess76', was gratuitous and not at all in keeping with the spirit of the forum, and your overly aggressive self-congratulatory attitude are not appreciated. I've got a 323Ci, a Z4, and a workhorse 318ti to look after, so that's why I don't jump right up and dump $800 on a full set of wires. Yes, that IS the price here in Canada for all 4 wires. It's not how much you make, friends, it's how much you keep.) I'm outta here.

[aayp170]

...

[aayp170]

...

[ChItalian1027]

did u try retightning the spark plugs???

[aayp170]

did u try retightning the spark plugs???

I installed new spark plugs.
Now my check engine code tells me "camshaft timing sensor" is at fault. I wonder if that's the main fault here, and if so, how do I go about replacing that sensor.

[scabzzzz]

im pretty sure you can find a bentley entry online if you search around. I've got an adobe acrobat version of the bentley i might be able to take a screen shot of for you if you wanna do it.

you still didnt get to the point of why you think cylinder 3 is misfiring. if you're throwing a code for it, the sensor is probably on its way out but tell us a little bit of the history first before we start tearing into the motor.

[ChItalian1027]

yeah i agree with scabzzz

[cooljess76]

(However, the slur, "it's pretty ghetto to change just one (wire) if you ask me," from 'cooljess76', was gratuitous and not at all in keeping with the spirit of the forum, and your overly aggressive self-congratulatory attitude are not appreciated. I've got a 323Ci, a Z4, and a workhorse 318ti to look after, so that's why I don't jump right up and dump $800 on a full set of wires. Yes, that IS the price here in Canada for all 4 wires. It's not how much you make, friends, it's how much you keep.) I'm outta here.

No need to be a fuckhead about things. "scabzzzz" is more than likely right. He works at a very reputable shop and he deals with these issues everyday. Perhaps you'll appreciate his knowledge and "attitude". It sounds like you have a pretty nice collection of cars. Too bad they don't receive proper maintenance. As for dumping $800CDN on a set of wires, if you do you're an idiot. Is that a dealer quoted price? Here's a few that I found without even searching too far, it literally took less than five minutes to pull these up:

BavAuto 8mm Plug Wires $170.95

Magnecor 7mm Plug Wires $85.41

Ebay BMW High Performance Wires $117.80

Not sure why I even bothered helping you, since I'm not a true "hotrod hobbyist." You're welcome anyway though. BTW, I don't think the wire is the problem, I just thought it sounded strange to replace just one wire and not all four. If I were you, I'd work with scabzzzz and tell him how you came to the conclusion that cyl3 was misfiring.

[ChItalian1027]

ok guys lets not piss each other off cooljess dude u have to calm down!!

[aayp170]

Here's the whole story. I bought the car for my son. Theoretically he wanted a ti, Ascot green, A/C, tint, sunroof, 5 speed, ASC, and leather so I found one and bought it on ebay. Perfect fit. Did a few repairs (replaced driver's window regulator.....easy job, replaced thermostat), added M3 rims and 17" Michelins, and it's a big hit. Check engine light came on so I attached the Peake tool and got the codes. "Catalyst efficiency" tripped the light twice, "misfire cyl. 3" tripped it first, however. That's when I ran the querry about the plug wire. Next code fired was "camshaft timing sensor." This car's our workhorse, so I won't throw money at it. I've just started toying with the car, and I'm finding that it's quite solid, rust free, and strong running. I generally overmaintain my cars, but this used car has to prove it's worthy before I chase it. If it turns out to be not worth it, it's gone, and I'll replace it.
scabzzz, if you've got Bentley info, I'd be very appreciative. Also, of all the brands of plug wires available, how can you know which are legitimate quality and which might be offshore fakes? I know aftermarket are not recommended. Lastly, would you know how accessible the camshaft timing sensor is on a ti, and does Bentley give instructions on R&R for that?

[bill k]

I doubt that camshaft sensor code is related to the misfire code. I also have been getting occasional codes that read misfire in cyl 3 and misfire in cyl 2. The lights come on and go off just as quickly. The code reader reads the stored code, so this is a "glitch" in the ignition. I changed the plugs but the problem persists, leading me to think it's the coils since the plug wires look fine.

[cooljess76]

Check the rubber boots going to the throttlebody. I bet one of them has a crack. I had a misfire cyl 3 and random multiple cyl misfire code on my last 318ti. I found a couple of splits on the flex boot between the MAF and the ASC valve. Sealed them up with epoxy, cleared the code and it never came back. Epoxy or RTV works for a temp fix, obviously you should ultimately replace it if it's cracked. You could also try to fog some brake cleaner in the general area of the intake plumbing and see if you get an idle fluctuation while the car is running. I know it's sort of off the wall, but it's a cheap and easy check before you drop a bunch of cash on coils. Hope that helps, sorry I didn't think of it sooner.

[ADRNLN_ti]

I’d like to know more…

I have a 98 ti and suffered the “cyl 3 misfire” for most of last year. It started out with an occasional CEL for C3M but it would also clear itself (never having any drivability issues). Then I started having ASC startup failures, you know when you start the car and the ASC does a self-test, finds something wrong, shuts itself down and illuminates the ASC light.

Well, I started having a actual misfire. The misfire would be anything from a mild hesitation like bucking a head wind to cutting out and wondering if I would make it up a hill. It was suggested that I unplug the ASC/ABS computer (located under the glove box, vertical next to the door opening). Unplugging the computer eliminated the problem so I knew then it was the ASC that was causing the misfire and nothing associated with spark.

My ASC codes were for the solenoid and the secondary throttle position sensor (opposite the solenoid). The TPS was a $52 part so I started there and viola’ no more misfire and the ASC started working !!

Sheridan

[scabzzzz]

Here's the whole story. I bought the car for my son. Theoretically he wanted a ti, Ascot green, A/C, tint, sunroof, 5 speed, ASC, and leather so I found one and bought it on ebay. Perfect fit. Did a few repairs (replaced driver's window regulator.....easy job, replaced thermostat), added M3 rims and 17" Michelins, and it's a big hit. Check engine light came on so I attached the Peake tool and got the codes. "Catalyst efficiency" tripped the light twice, "misfire cyl. 3" tripped it first, however. That's when I ran the querry about the plug wire. Next code fired was "camshaft timing sensor." This car's our workhorse, so I won't throw money at it. I've just started toying with the car, and I'm finding that it's quite solid, rust free, and strong running. I generally overmaintain my cars, but this used car has to prove it's worthy before I chase it. If it turns out to be not worth it, it's gone, and I'll replace it.
scabzzz, if you've got Bentley info, I'd be very appreciative. Also, of all the brands of plug wires available, how can you know which are legitimate quality and which might be offshore fakes? I know aftermarket are not recommended. Lastly, would you know how accessible the camshaft timing sensor is on a ti, and does Bentley give instructions on R&R for that?

No need to be a fuckhead about things. "scabzzzz" is more than likely right. He works at a very reputable shop and he deals with these issues everyday. Perhaps you'll appreciate his knowledge and "attitude". It sounds like you have a pretty nice collection of cars. Too bad they don't receive proper maintenance. As for dumping $800CDN on a set of wires, if you do you're an idiot. Is that a dealer quoted price? Here's a few that I found without even searching too far, it literally took less than five minutes to pull these up:

BavAuto 8mm Plug Wires $170.95

Magnecor 7mm Plug Wires $85.41

Ebay BMW High Performance Wires $117.80

Not sure why I even bothered helping you, since I'm not a true "hotrod hobbyist." You're welcome anyway though. BTW, I don't think the wire is the problem, I just thought it sounded strange to replace just one wire and not all four. If I were you, I'd work with scabzzzz and tell him how you came to the conclusion that cyl3 was misfiring.

Thanks cooljess! I see you on all the forums haha.

But yeah, the misfiring code, all I wanted to know was how you knew that it was cylinder 3, aka, telling us that you ran a Peake tool and check the faults. Thats all I wanted to know. You dove right in without background info. But basically, I think some of the issues the guys in the previous responses have gone through are really valid. Im not top notch on the m42 and m44 motor, since I've never ran that motor in my car, but more than likely you're throwing a camshaft sensor code because you're misfiring. Check the intake elbow for cracks along with your charcoal cannister (I think your model has one sitting in the engine bay underneath the elbow behind the air box), probe around and see if you can find any vacuum leaks. And start from there. You can do so by taking a rubber hose and putting it up to your ear, and moving it around the engine bay. you'll hear a distinct sucking noise when you hear a leak. Make sure the engine is on. Good way to see where faults are. After that, just keep clearing the codes and see which ones come back. If cylinder 3 misfire keeps coming back, replacing the plug wires probably wont really help. Although, it wont hurt at all. As far as replacing the plug wires with OEM, not so much. I mean, they are all going to pretty much do the same, and unless you're really specific on ignition for race purposes, it wont matter. Just buy some decent ones at a local parts store and get a set of Bosch or something similiar. Probe for vacuum leaks first, as OBD-II models are very reliant on a steady vacuum throughout the air induction stage in order to provide a consistent air-to-fuel ratio. You probably wont be able to pass emissions with this code.

[cooljess76]

I’d like to know more…

I have a 98 ti and suffered the “cyl 3 misfire” for most of last year. It started out with an occasional CEL for C3M but it would also clear itself (never having any drivability issues). Then I started having ASC startup failures, you know when you start the car and the ASC does a self-test, finds something wrong, shuts itself down and illuminates the ASC light.

Well, I started having a actual misfire. The misfire would be anything from a mild hesitation like bucking a head wind to cutting out and wondering if I would make it up a hill. It was suggested that I unplug the ASC/ABS computer (located under the glove box, vertical next to the door opening). Unplugging the computer eliminated the problem so I knew then it was the ASC that was causing the misfire and nothing associated with spark.

My ASC codes were for the solenoid and the secondary throttle position sensor (opposite the solenoid). The TPS was a $52 part so I started there and viola’ no more misfire and the ASC started working !!

Sheridan

Great advice and excellent writeup!!!

[aayp170]

Great input. Thanks. I'll check into it.
By the way, Cooljess76, I have the same M3 wheels on this ti, and I was wondering how much lower the car can go if I use 225 x 45 x 17" tires on these rims.

[tonyfox1956]

Why not change all of your wires? I mean it's pretty ghetto to change just one if you ask me. I've heard a few stories about people checking their spark plugs to find out that they don't all match. It's no wonder why these people's cars don't run properly.

You arrogant pig, not everyone wants to or is able to throw money away replacing everything. This person is trying to diagnose the problem!