Help please! won't start...

[JayVroom]

Ok, so my '98 jetta glx w/ 147k left me stranded at the grocery a few nights ago. I recently replaced the pre-cat O2 sensor, had too lean code cleared, and then it came back 3-5 days later. Kept driving it but thought I should perhaps replace fuel filter...only had car since 128k, so who knows age of said filter. Anyways, had not gotten around to replacing before the grocery trip. VW stalled as I pulled into parking spot, and then would not restart. Has ample gas in tank btw. Cranks fine. So I thought, replace cheapest parts first and try to diagnose...replaced 167 relay, still no start. About to do filter if rain will stop. Can smell gas when pedal pumped while trying to start tho...read numerous posts, think crank position sensor possibly bad? or other problem? Thought about coil pack, but no missing prior to stall...suggestions? Please help!!

[JayVroom]

anybody got ideas?

[llanowar]

its possable crank sensor but most likely ecu


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[llanowar]

ive never had a bad crank sensor on a vr has ur ecu been chipped ? recently


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[JayVroom]

yeah, i installed a UM chip 1-2 months ago...why? they get great reviews on here...changed fuel filter but no change and it wasn't that dirty. Have new crank sensor but hate to replace if not culprit, as it was ~$100!...

[JayVroom]

also, it seems my low oil level light is blinking upon cranking, however there is ample oil acc to dipstick...?!? I'm a noob I guess, but this seems odd...wtf?!

[masterqaz]

Check for ignition, pull plug leads while someone cranks it over, be careful not to ground yourself to the engine by touching it with your other hand, might suck if you do

Do you still get a cel light when you key up the car?

[ps2375]

Have it scanned for codes. Can this be so hard? It will stop the guessing.

[JayVroom]

scan only shows too lean mix (still)...already checked spark, all good there, as recently did plugs and wires, coilpack amazingly still doing its job too. Replaced blue oil pressure switch last night, no fix, waiting on black switch today and coolant temp switch. Other ideas?

[JayVroom]

Wondering if I should pull the UM chip and try the OE...although chip has been in for ~2 months and no problems til this week. Gotta dig up the OE chip too! ugh

[ps2375]

Can you hear the FP running when it doesn't start? There will be no codes generated when the FP fails.

[JayVroom]

I can't hear it, altho I never really have been able to...already popped the cap on it, guess I'll get the wifey to turn the key while I put my hand on it...I did smell gas when trying to start, especially after pumping the gas pedal! there was gas in the fuel filter upon changing as well...replacing sensors now...

[ps2375]

A check of the fuel press would be a good thing too...

[JayVroom]

ok, coolant temp sensor changed, high press oil switch changed, also can hear fuel pump working...now feeling outta obvious answers/quick fixes. Guess I'll try to fire up car via spray into TB, and go look for OE ecu....

[JayVroom]

Still flashing that damn oil light...wtf!! both sensors replaced, freaking plenty of oil in engine...am I missing something glaringly obvious!

[JayVroom]

My VW remains in the driveway...anybody have any further suggestions? Bump for info about blinking oil light continuing after replacing both press sensors...? Thanks!!

[JayVroom]

bump for further help please! Most cheap parts replaced now...

Am I correct in seeing one crank pos sensor on front (white plug?), one cam pos sensor on front (black?), an engine speed sensor by coilpack, and another cam pos sensor on back (white?)...if not, please feel free to inform my confused self!

[GTIVRon]

Can't really comment on colors, because most of my sensors down there are black now...

But the crank position sensor is up and to the right above the oil filter housing. Pretty sure it is 3 wire, but might be 2. The other sensor you are seeing in the vicinity is the knock sensor. The cam position sensor is right where the "back" (bank 1, cyl 1,3,5) cam gear is. The "engine speed sensor" is the crank sensor.

You said you bought the crank position sensor? Replace it. I bet that fixes your problem.

[Kadams29]

^ thats my guess also, and if that doesent work swap either that chip out for the Oem and/or a different Ecu. They do fail from time to time its just not frequent. But the chip could be faulty. Could of goTten hott and melted a solder joint. Gl buddy.

[JayVroom]

Thanks for the input guys! I had actually returned the Crank sensor to advance auto for some reason and am now glad I did...as I realized this morning that I needed to do LOTS of maintenance on the vw AND that I should be ordering all my parts from autohausaz.com instead. So I ordered the crank sensor again, as well as oil pan gasket, oil cooler gaskets, valve cover and intake mani gaskets, all for the price of just the sensor from advance! I did swap back in my functional OEM ecu yesterday, but no change from UM chip. I will inspect the oil pump tomorrow, as I stripped the 25th of those damn 26 oil pan screws...

Thanks again!

[GTIVRon]

The oil light comes on when pressure is low. When you are cranking, the RPMs are extremely slow compared to a running engine. Thats why it doesn't maintain pressure and the light flashes while cranking.

Also, when you were cranking did you happen to see if the tach needle moved or jumped at all?

Before you drop the oil pan for no reason, install the new crank sensor, car should start then, and then you can see if the oil light stays on or not.

[JayVroom]

Thanks again for the info and reply! The tach needle does pop up about one hash mark when cranking. I have already pulled all but that one oil pan bolt, so will prolly go ahead and replace gasket at least, Everything down there on front side of block is pretty heavily coated in oily grime, presumably mainly bc leaking oil cooler gaskets that I've been meaning to change for a while...figured I'd do those since oil already drained and oil filter actually looked a little odd, as in kinda sucked in like in a vacuum or something...weird. Oil/filter wasn't even 5k old tho. Fingers crossed for CPS fixing starting issue tho!

[vdubCorrado]

use OEM oil filters from the dealer...

i had a no start, cranking and fuel situation on my Corrado VR6 and it was the Engine Speed Sensor/ Crank Position Sensor. i replaced it an immediately started seeing spark again. only took 2 tries to start right up...

[JayVroom]

right on...yeah got a new Mann filter n Mobil 1 oil...will install cooler rings, oil pan gasket, CPS, new oil n filter...then listen for that vroom! pan just pulled, noticed no metal shavings or other oddities upon first inspection...makes me rather hopeful that oiling system is intact, although new gaskets were certainly needed!

[denver412]

Man there is a lot of not starting going on. So I am having the same no start issue. Researching posts, I first replaced CPS. Not it. ECU and FP relays fine, pump running.

Now I am testing my coil (distributor VR6). I am finding that my coil should read between 3-4 Ohm. Question. My ohm meter has 200 as the lowest test setting. Does that mean I should be looking for .3 to .4? My coil is reading .8-.9.

Can a fuel pump run and yet not pump? Mine runs but when I take the pressure test cap off the rail and turn over, no fuel comes out. New filter.

Thanks

[JayVroom]

hey denver, sorry to hear bout similar vw woes. I am certainly learning here, and am curious as to your initial no start circumstance...did it stall out on you, or just not start one day? Any CELs?

[denver412]

It started about three weeks ago by just every now and then the engine cutting off and on while driving. Like literally for only 2 seconds. Then it went to a sometimes not starting until 3rd try issue. Then it moved to a sometimes stalling at stop lights but started back up. Then last week it stalled totally but started after an hour. When it started, I drove for less than a mile and it stalled and has not started since.

[vdubCorrado]

Original poster, did you check your oil pick up tube for pieces of timing chain guides in the pick up while the oil pan was off?

[GTIVRon]

On the dizzy motor issue, check the wiring for the CPS.

Are you getting spark? Check the rotor, see if it broke and turned far enough of where it won't spark (recently had that issue), if thats not it, see if it rotates freely with the engine stopped, that was another issue i had with a brand new bosch dizzy. The "coupler" piece to the camshaft broke.

On the dizzy coil, I'm assuming that .9 ohm you are reading is between the two "posts" behind that little door? That .9 ohm is fine. Measure between the one closest to the front of the car, and the output end that feeds to the wire that goes to the center of the distributor. That should be a couple thousand ohms. Mine read in the 7k-8k range, even though the bentley says 3-4k. A brand new one read around 7K.

You need to figure out if you're not getting spark, or if you're not getting fuel. I don't trust that little nipple on the rail. Disconnect the fuel feed (top one) and then have somebody crank, it should spray fuel for a good bit, so stick the end into a bottle to avoid making a mess. Then you'd have to check voltage at injectors (access to cyl# 1 is simple enough) since the ECU controls that.

To see if the ECU is sending spark signal out, disconnect the 3 pin connector from your ignition coil, and put a test light into the middle pin (#2), as you are cranking, your test light should be flashing. The signal there is 12v so most test lights should work fine.

[denver412]

With my ohm meter set on 20K, it reads 7.60 between the high and either one of the terminals, #15 or #1. I have the coil disconnected from the sender thing that attaches to it. Thoughts on that reading?

I will check out the fuel via the input hose in a bit. I was kind of wondering about that test port!

Thanks

[GTIVRon]

My old one is (that is still in the car and working) reads over 8k. My brand new one reads near 7.5k.

Have you established that you are getting spark yet? Pull one of the plugs out (unless you happen to have a working good plug laying around) and connect it back to the wires, ground it against the block, have somebody crank, and see if there is spark. Do this for at least 3 wires.

Also, take the ECU out (very easy, lift leaf tray cover, remove the cabin air intake screen thing, disconnect the harness to ecu by pulling on that T and sliding it off, then 1 10mm nut and just work the ecu out near the left side), open it up (4 torx screws) and inspect the board. Just look for somethign that looks burnt. What has happened to me (and i saw it here a few times) is the chip worked its way out of the socket. So check that too.

[JayVroom]

wanting to keep this thread alive until our problems are resolved, as I hate threads without helpful conclusions for other followers in need, but alas my parts have not come in yet. However, I pulled my upper intake mani and valve cover for maintenance etc and need help understanding the procedure for removing the lower mani...? yeah I don't have a bentley. help appreciated, as I don't want to damage fuel rail, injectors etc. Thanks!

[JayVroom]

alrighty, parts in from autohausaz! Got crank pos sensor in, now to do oil cooler o-rings and valve cover and oil pan gaskets...still no love on the lower intake manifold removal??! scared of the fuel rail...

[Ginster_Mk3]

I had same issue a year ago. Car would crank up fine but die immediately. If I leave it alone for an hour and come back it would start right up. After pulling a couple hairs out not being able to figure it out a friend of mine suggested the CPS and had no issues with it after that...........

That is until this past month. Car had died on me twice now. Cranks up thend dies. It can not be the fuel pump as I would imagine after trying to crank it a couple of times it should eventually not even really crank but no it cranks fine evertime like it is getting the fuel. I still think it is my CPS but now have to figure out why it keeps failing. I have a new one in.

Anyways good luck on the fix.

[JayVroom]

Thanks! So curious...did new CPS fix it? finally getting around to putting all of mine back together this weekend hopefully, so fingers crossed! Still unsure how to go about removing lower intake manifold tho...