Car won't start...help appreciated.

[gsav69]

My car is 99 GTS with Vec1, exhaust work and otherqise fairly stock. Last weekend I took the car out to get it washed and it fired up just fine. I started it and sht it off a few times and at one point I fired it up at the car wash and it violently backfired and then wouldn't re-start. I smelled gas and it felt like it had no spark. I noticed the VEC1 gauge wasn't on so i reached under the dash and tugged on the VEC wires and the gauge started to read (or at least read a lil differently), and the car fired back up. I drove it home and parked it so as not to get stuck.

Today I went to start the car and it backfired violently and won't start again. It turns over and I smell gas like crazy but it won't fire. If I leave the key on for a few seconds i notice that the far right blue VEC light stays on and after a few seconds it starts to cycle the first 2 lights, then a few seconds later the first 3 lights cycle and so on, until the lights get to the middle. I'm not sure if it normally does this because I've never paid attention.

I assume the coils can't be bad or the car would at least start, unless they're all fried. Without diving too much into it yet I'm guessing some loose wires on the VEC, a bad VEC or bad PCM.

Any ideas and help would be appreciated.

 

[Limit]

check fuses.

 

[uvbnbit]

No CEL's either?? I'm not sure if VEC1 has anything to do with the starting, i.e. did it get wet? cam/crank sensor?

 

[gsav69]

The VEC def didn't get wet. The car cranks like crazy, just won't kick. I was alone today and wasn't dressed to start yanking plugs and checking for spark. No CEL's that I've seen since I bought the car 3+ years ago.

I had a thought. If I unplug the VEC t-taps under the dash and/or disconnect it's ground, will that disable the VEC yet still allow the car to start?

 

[Chuck 98 RT/10]

How old is the battery?

 

[gsav69]

Car is always on battery tender and cranks just fine. I haven't changed it in the 3 years I've had the car.

 

[99 R/T 10]

cam/crank sensor?

That would be my guess.

 

[gsav69]

OK. I'm leaving on business and then when I get back I'll try and troubleshoot it. Any and all tips are appreciated! Thanks so far!

 

[speedracervr4]

Call Sean at Roe 9042305422, he'll be able to help you out. I don't believe the VEC affects the starting or idle.

 

[BOTTLEFED]

Well the VEC1 does tune timing, so it has to tie into the ignition system somehow.
I can't remember now because its been awhile, but the VEC1 wiring all taps into the harness right at the PCM. I would trace them out from there and under the dash and make sure they aren't pinched or shorted out. This is my first guess from your description.
You may have lost crank sensor signal because of it.
My other guess is the crank sensor itself. It is on the pass. side of the block near the motor mount. It's the one with the little foil shield over it. A single bolt and the oring hold it in.

 

[Bobpantax]

If I recall correctly from when I had my 1999 GTS with a Roe supercharger and a Vec 1, Sean specifically said that the unit can not be subjected to direct water. He told me that when I washed the car that I should put a plastic bag over it if there was any chance of some water being sprayed at it while the car was being washed. I did something a bit different. I had Sean make me a protective box for the unit attached by double sided velcro. If somehow ,while it was at the carwash, water got into the Vec unit, it would account for your problem.

 

[BOTTLEFED]

I think some of you are getting the VEC1 confused with the VEC2/3. The VEC1 was a completely different unit. It looks and functions totally different than the current VECs. The VEC1 was completely mounted inside the car, usually near the driver, with the afr gauge on the steering column. The only part under the hood is the wiring to the PCM. There's not really anything to get wet.

 

[Bobpantax]

What about the card reader? Where was it located in this case or wasn't there one?

 

[BOTTLEFED]

No card reader on the VEC1.
It was simply 2 knobs for adjusting timing and fuel. It didn't work all that well really. Sean doesn't even recommend using them any more.

 

[Bobpantax]

Thanks. You are right. I must have had the Vec 2.

 

[gsav69]

Hey guys. Just back from traveling. The Vec 1 has never been close to water. It def wires into the ignition system in that the unit adjusts fuel and timing at both low and high throttle. I'm just curious if disconnecting it may allow me to see if the car will start in stock form. I have the original instructions but don't know too much more about this unit or troubleshooting it. I may give Sean a call tomorrow.

 

[2000acr]

1) Disconnect the engine harness from the vec and plug the factory harness back in without vec- see if it starts- if it does check your vec wiring-

2) If the vec wiring is good- and it dosnt start with the factory harness in place- check the cam position sensor- its cheap to replace 35$- and your symtoms are exactly what happens if its bad-

3) if not the cam position sensor the crank pos sensor-

 

[gsav69]

Thanks 2000ACR. The vec 1 gets t-tapped into the stock harness under the dash and at the PCM, the stock harness does not get plugged into it. I'm going to do some troubleshooting in next few days when I have some time but here's my question. I'm getting Fuel for sure in the smell from the tailpipe but I have a feeling there's no spark. If the injectors are getting a signal to fire, would that indicate that the cam/crank position sensor are functioning? I guess what I'm saying is, if they aren't functioning would the car know to still fire the injectors...if that makes sense? Thanks.

 

[RevHeat]

I suggest you get rid of that VEC. It will just cause problems.

 

[plumcrazy]

vec1 isnt a great unit anyways, might want to install a vec3 or something else and start fresh from there. but a new battery isnt a bad idea. its obviously older than 3 years

 

[gsav69]

I figured when I went forced induction I'd go AEM or otherwise and didn't assume it would $hit the bed on me! Im not a fan of this thing either but it seems to work fine for a car thats virtually stock with exhaust work and some minor stuff.

 

[speedracervr4]

Should be able to check for spark by pulling the plug wires off the spark plugs and having some one turn it over. Should see the spark from the plug wire.

 

[uvbnbit]

We've got a member selling a VEC3 if interested. 1/2 price, I think???

 

[gsav69]

I was by myself the day I was diagnosing the car and couldn't pop a plug wire off, check for speak and turn the key and I didn't want to jump the relay and short something out! I'll def take a look at it in the next few days. Thanks to everyone for your advice.

 

[gsav69]

So the Viper is back alive and have I learned a valuable lesson. First off, you definitely need shop manuals (which I have), including the owner's manual (which I don't have). Secondly, don't use your nose to diagnose the problem, use the forums and listen to the first person to reply...THANK YOU LIMIT!

I had fuel puking out of the exhaust when the car was cranking but no spark. I believe the ASD, Automatic Shut-Down Relay was actually working. The day it broke down, I had run the car farily low on gas. Not where I thought it was empty but very low. When I was at car wash I put a gallon or 2 of gas in it and it fired up shortly thereafter. The reason it took a few minutes was probably because the plugs were fouled a bit. When it started it stumpled for a few mintes and ran fine for a little while til I brought it back to the garage.

I believe i ran it out gas again and didn't realize it and actually popped the Fuel Pump Fuse located in the back of the car...which I had no idea about because I never needed to look for it! The shop manual calls for a 25amp fuse (the only normal size fuse in the whole car...the rest are mini's) and my fuel pump had a 10 amp in it. I can only guess that I ran the pump dry and it got so hot it popped the fuse or the pump is clogged or going bad.

Needless to say, we noticed it had some fuel pressure in the rail but wasn't getting spark. After much diagnosis we located this fuse block in the back and found the culprit.

I guess the real lesson is, always start in the beginning by checking all relevant fuses and even if you smell gas, it doesn't mean your getting any! Lastly, I've popped a Fan Relay this year and this fuse which is different than all the rest. Let's just say you'll find an extra fan relay and a bunch of fuses in my glovebox!

Thanks to all for your help and sorry for the long-winded update!