Random No Starts with Key

[CiPHeR]

Heya everyone...

99 2.0 Gas, 5spd standard... was having issues with this starting last summer (right after my warranty expired) Have a K&N filter charger (box type) which I replaced back to factory this weekend. Anyways, the problem is this: Every now and again, the car just doesnt want to start - it turns over just fine, just doesnt seem to fire. Usually, if I leave it for 15-20 minutes and come back and try again, it will start. Or if I am on a hill, I can put it in 1st, roll down the hill with the key on, and pop the clutch and it will start.

A few days ago, I took it into the local dealer to have them do diagnostics and they informed me it was my Mass Air Flow Sensor and my Engine Speed Sensor that was causing the no starts... keep in mind that if I tried too many times to start it the first time, when it does start, the check engine light comes on. MAP and ESS was gonna cost me around $600 CDN plus tax to have installed, and no guarantee that it would fix the problem.

Spoke with a couple of other VW and non VW techs, and somewhat agree that it doesnt seem like the MAP and ESS... another dealer said it seemed like it could be a communication problem between the ignition switch and the ignition module. It is a very inconsistent problem and very random. I can go weeks without this problem, then all of a sudden, last week and had problems almost everyday.

I am at a loss, and dont have the money to start dumping into electrical troubleshooting. Any ideas, suggestions would be greatly appreciated.

Thanks,

[hannaco]

Well, first get a list of the codes. Once you have that, a plan of action can be made.
Lots of things can cause similar problems.

[SilverSportNOLA]

That is MAF not MAP .... and for a bad MAF you can always unplug it to see if it is the problems.

Of what I recall .... this sounds like the same problems others in the 99-2000 models had when the ignition switch failed. There is also the fuel pump relay that could cause this problem ... it did in my 85 Dub.

[kcfoxie]

My 98 had this problem but ONLY after it was driven at op. temp. for "extended periods" in excess of 15 mins. My problem turned out to be a failing cyl #3 and a leaky headgasket, but the problem had been ongoing for months prior to my owning the car. I hope yours is just a relay or speed sensor.

[CiPHeR]

Okay, I changed out the K&N filter for a stock filter and had to disconnect the MAF sensor... forgot to hook it back up and drove around all day friday like that... well, as you can imagine, the car stalled out on me several times, wasnt until later that I realized the MAF was unplugged. Plugged it back in, car worked fine all day saturday, then saturday it would not start again. Tried leaving for 20 minutes and tried again... still no start... repeated 2 more times, still no go... tried bump start, no go, now key starts car... Car worked fine all day sunday with the exception of one stall at a traffic light but started on the second attempt. Car worked fine all day monday, most of the day today, but I went to move it at work, almost started - caught, fired, then died... wont start now no matter what I do, key, bump start, waiting 20 minutes, or 2 hours... can smell gas at the tail pipes... I am at a loss and getting really frustated with this problem as I cant figure it out... and since VW wants $600 plus to change the MAF and engine speed sensor, not liking that option

[GTRAFF]

My 98 did the same thing. It was the engine speed sensor. It is a little sensor near the oil filter and frequently has intermittant failures especially when hot or cold. The easiest way to check it is to observe the tachometer when cranking the car to start it. The tach should move. If it does not move then the engine speed sensor is not producing an output signal and the car cannot start. It is the only sensor used to start the car. After the car starts it is not used - in other words if it goes bad while the engine is running the engine keeps running although the timing will be retarded to compensate. I think the sensor was about $40 - $50 but very difficult to change. You need small hands!!

[CiPHeR]

Okay, went and checked the tach while turning over, no movement on the tach... so, I guess that means the Engine Speed Sensor? Since the MAF was unplugged for a full day of driving on Friday, would that have caused any other problems?

[SilverSportNOLA]

No .... the maf unplugged will make it run a little rich ... open loop is how the car runs until it comes up to operation temp ... then the maf starts measuring airflow and fuel mixture is richened or leaned based on the airflow through the MAF. It should not cause a problem. Hope that speed sensor is the key.

[CiPHeR]

Okay guys, thanks for all the help and the input... it is GREATLY appreciated... I will keep you posted...

[GTRAFF]

By the way, the Bently forums have a thread on changing the engine speed sensor with pictures if you get stuck.

[CiPHeR]

Originally Posted by GTRAFF

By the way, the Bently forums have a thread on changing the engine speed sensor with pictures if you get stuck.

Do you have a link?

[GTRAFF]

I am sorry, I don't have the link. If you go to the bently forums and search for engine speed sensor you should find it pretty easily. It is one of the sensors Bently did not do a very good job explaining in their manual so there are several threads about it.

[spe1983]

Sounds similar to my wifes '98. Random no starts that eventually led to a constant no start. After I got stranded at the grocery store and had a gallon of milk go bad, it started after about an hour later and made it home. Next day bought the ESS sensor at the dealership for $125, I think you can get it on ebay from FCPgroton for about $55 http://cgi.ebay.com/ebaymotors/Audi-...spagenameZWDVW.

It is a complete pain in the ass to change. You will get oily and a cramped hand. Best way for me was to remove the air pump(you might not have one), disconnect the wire(its real close to where the air pump connector is), remove the bolt holding the sensor in place from above(need an ratchet extension), get the wire unrouted, and hard tug on the sensor will get it out. Installation is a little quicker, but a nice hard push will get the sensor seated properly.

I think it took me about 45 minutes to do it, theres alot of hoses and junk in the way. If you can easily remove the fans I think it would make this a breeze, but im not sure how long that would take. Not too hard but very little room, and all the oily mess on those hoses makes it a PAIN. Good luck

[GTRAFF]

I looked up the thread on Bentley forums. There is a link to a picture showing the sensor locations. Good luck - pain to change!!
http://tech.bentleypublishers.com/th...=230824#230824

[CiPHeR]

Originally Posted by spe1983

Sounds similar to my wifes '98. Random no starts that eventually led to a constant no start. After I got stranded at the grocery store and had a gallon of milk go bad, it started after about an hour later and made it home. Next day bought the ESS sensor at the dealership for $125, I think you can get it on ebay from FCPgroton for about $55 http://cgi.ebay.com/ebaymotors/Audi-...spagenameZWDVW.

It is a complete pain in the ass to change. You will get oily and a cramped hand. Best way for me was to remove the air pump(you might not have one), disconnect the wire(its real close to where the air pump connector is), remove the bolt holding the sensor in place from above(need an ratchet extension), get the wire unrouted, and hard tug on the sensor will get it out. Installation is a little quicker, but a nice hard push will get the sensor seated properly.

I think it took me about 45 minutes to do it, theres alot of hoses and junk in the way. If you can easily remove the fans I think it would make this a breeze, but im not sure how long that would take. Not too hard but very little room, and all the oily mess on those hoses makes it a PAIN. Good luck

Hey Spe1983,

One question, sounds like my same problem... used to start 15-20 minutes later, but now it takes 2-4 hours before it will start. Did replacing the ESS solve your problem? How long ago did you replace it?

I am actually looking at trading it in (while I can still get some decent coin for it) for an '03 Jetta GLS 2.0 Gas.

Thanks again guys!

[CiPHeR]

Okay, update time... just changed out the mass airflow sensor... going in monday to the dealer for the Engine Speed Sensor. Car runs, but blowing a lot of white smoke... Replaced the K&N Filter for a stock filter, smell gas, seems to be running a bit rich... Would that be a combo of replacing the bad MAF Sensor and changing the K&N back to stock?

Thanks

[CiPHeR]

Update time... Okay, dealer replaced Engine Speed Sensor on Monday... problem seems to be fixed. Considering the car had gotten to the point where any time I had driven the car for more than fifteen minutes, after 30 minutes of being parked the car would not start again for at least 2 hours or more. So far, so good, car has started each time, regardless as to how long it was running, and how long it had been parked. Stock filter and new Mass Airflow Sensor in conjunction with the new ESS, car seems to be running like new now!

Thanks for the help everyone... case closed - I hope!

Cheers