Blown ignition fuse at the track

[deyan]

Hi, new to this forum, I acquired a 96 GTS racecar last year, car was done by woodhouse and the engine is from Exotic Engines.

Car has been running great until my last track event, I did about 10laps, and on the cooldown lap as I slowed down the car went quiet.

It cranks over, but does not start. We found that the 30amp ignition fuse was blown. Replaced it, but still nothing.

I am going to plug in an obd2 reader this weekend and see if anything comes up. So far, it seems like the injectors are not firing, not sure about spark, fuel pump primes.

Any ideas would be appreciated!

Cheers

 

[Steve-Indy]

Common racing situation with Gen II was to have fuel pump relay vibrate loose...try to reseat that relay before going too far. This tip given to me by friend Sean Roe after a problem in 1999 World Challenge race...as I recall.

After that, careful systems analyses may yield fruit.

Good luck !!

 

[deyan]

Thanks I'll check that, but not sure that would cause the ignition fuse to go.

I just checked for codes and I am getting P0320 ignition/distributor engine speed input circuit

Any ideas? Crank sensor?

 

[Steve-Indy]

Now that you have found no spark, sounds like ASD problem(tried swapping ASD relay?)..though, now yet into cause or direct answer to blown ignition fuse. Possible bad coil or ignition switch? PCM may also come to be question.

Again, to me best step is connect up to DRB III to read system and component sensors. Start with crank sensor and wires.

Loose connection, melted wiring, loose or damaged connector come to mind. That will require lots of checking !!

One other issue is just what you mean by "racecar"...i.e., just how modified is it?

 

[deyan]

I have not tried the ASD relay, I'll see if I can find one. Today, I'll try swapping the ignition switch (its a toggle switch) and see if that makes any difference. Don't have a DRB III available to me, but I'll see if I can source that from somewhere, or maybe take the car somewhere.

The car was an SCCA GT-2 racecar, pretty much everything has been modified, except the wiring system and PCM (tuned). I have a cutoff switch, ignition toggle and push start button.

Thanks for your help!!!!!

 

[Steve-Indy]

Sorry I can't be of more help. Try swapping ASD relayy with a nearby non-essential relay.


By the way, our 99 uses a 40 amp ignition fuse.

 

[deyan]

Swapped the ASD relay with another, but still nothing. Might need to call Prefix for this one

 

[deyan]

So the blown fuse I think was a dead lead...I think it had been that way for a long time, I don't think its used in the current configuration.

I think something failed on its own, I don't think it was a short.

Checked for fuel pressure, all good, solid 50+

I'll run through the camshaft/crankshaft check procedure as noted in the service manual next. At least its a good opportunity to learn more about these cars, hah.

 

[MoparMap]

Yeah, the "standard" troubleshooting for an engine not starting is air/fuel/spark. Air is pretty easy to check, you've checked fuel, and you know that spark isn't exactly working based on the code. Technically speaking the fuel could still be suspect as having fuel pressure doesn't guarantee that the injectors are firing, but you know there is at least fuel in the rails. A cam or crank sensor seems like a good bet for the ignition not working. Hopefully your testing yields some answers.

 

[deyan]

So I did the service manual test procedure, and I am getting

• Crankshaft position sensor 5 volt supply circuit
• Camshaft position sensor 5 volt supply circuit
• Crankshaft position sensor 5 volt output
• or ground circuits

Camshaft circuit (middle wire) is grounded, will check the crankshaft next.

 

[deyan]

It's got to be one of the sensors.

I am getting good ground, good 5V and signal reads to both crankshaft and camshaft circuits.

 

[MoparMap]

Don't suppose you have an oscilloscope of some variety? I got one as a Christmas present years ago that's a digital scope about the size of a cell phone. I'm sure it's not as super accurate as a real benchtop version, but it's great for dealing with varying signals like speed sensors. If you could tap into the line coming off the sensors you could see if you're actually getting a waveform or not.

 

[deyan]

Unfortunately I don't, I should get one eventually though, as it seems parts are hard to come by nowadays. For now I'll get new sensors and try. I found a camshaft sensor (non OEM, Walker), but crankshaft sensors have been impossible to come by.

Any ideas where I can source one?

 

[MoparMap]

Hmm, first thoughts would be trying somewhere like Roe Racing or maybe Parts Rack, though that's more the aftermarket side. They will sometimes carry hard to find stock parts though. The other alternative would be to call Don Scharf and see what they have. As a salvage yard I'm sure they would have access to them, but not sure how engine electronics tend to get salvaged. I'm guessing they prefer to sell whole engines, and if one blows up I'm not sure if they would strip them down for parts or not, but never hurts to ask.

 

[deyan]

Viperpartsrack had them! It seems rather unfortunate how quickly parts support is disappearing

 

[MoparMap]

Yeah, it's a funny mix. A lot of the parts are still shared between Chrysler platforms, so there is some decent availability, but when you get to the Viper unique stuff it can be tricky to find them. I think it might still be a while before Viper restoration companies open up as the cars really aren't all that old so to speak. The gen 1s are certainly getting there as they are almost 30 years old, but you figure a lot of the classic Mopar muscle car stuff is still only just becoming more available nowadays. I know you can get almost anything for a B body (for a price at least), but with my old A body the restoration parts are just starting to become more available.

 

[Daniel SRT-10]

I would like to know what prospect of finding parts will be, I’m sure at some point we will see aftermarket replacements frequent but the profit margins aren’t there to get involved in it at this time. There looking at a car that is pretty rare, but one thing from the aspect of sales has going for it most vipers get wrecked. But then again as time goes on people will be less likely to drive them because the cost to fix or just may not be possible to find a replacement part. It’s a tragic end but I blame the drivers that wreck them. You wreck a viper you destroyed a little part of what any European thinks of America.

 

[Shaggy]

Viperpartsrack had them! It seems rather unfortunate how quickly parts support is disappearing

Glad you found the part. You post up pics of your car yet?

 

[deyan]

As someone who works for the company, it is rather unfortunate that it doesn't do a better job of supporting it's iconic cars, but mostly it should be Mopars responsibility to do so. For now I guess I'll just try and buy parts before they disappear and slowly replace them with custom stuff.

Shaggy, just what's in my profile pic, I don't have many photos of the car.

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[deyan]

Crankshaft position sensor it was! Never even seen it fire up so quickly before haha.

Thank you all for the help!

 

[Steve-Indy]

Glad to hear that you are up and running !!