Blowing fuses with Mopar Controller and Engine Problems.

[vincy]

I have a problem that no one has been able to solve. The 2008 ran OK for a while with the Mopar computer then started running like a 1970 Plymouth with bad rings and valves.

First time it went to the Viper shop with a Viper tech he said there was water in 8 or 9 and 10. He looked inside and said all is well and it held compresion. The car ran ok for a short time the felt again like an old engine. I have the impression it was running on 8 cylinders.

Next time it went in the shop it got fixed then showed engind codes. Eventually the tech said a fuse was blown, the one in the top right row of the smaller center fuses. Pictures are attached

The car ran great for a while on a mixture of 75% 93 and 25% 100 octane. But if I get on it and do a fast 1st to 2nd shift the same fuse blows and the car goes into limp mode. This has happened about 5 times now. I'm not overreving the engine. It seems to be related to how hard I hit 2nd gear but this type of thing is hard to pin down.

Replacing th fuse solves the problem but it seems that the engine is either not running right or starts detuned. But the time it resets the tune the fuse is blown again.

The same problem has ocurred with two different Mopar computers. Mark J has been very helpful checking out the computers and sending a replacemnt. Viper support and Mark and the Viper tech Stan do not think the computer is at fault. I sort of agree because the car wasn't very strong before the Mopar computer was put in, but I'm not 100% sure about this. The car has been in and out of the shop so much I can't remember the whens and wheres.

I have headers. We don't see any obvious wires near anything that would short out.

This is really frustrating to the point I'm not interested in driving the car.

Stan the Viper tech says he does not think there is a head gasket leak, but I still suspect this. We don't understand why there was water in the cylinders but this hasn't returned. Maybe it looked like water because the plugs were not firing.

Does anyone have any suggestions? Thanks to all.

 

[plumcrazy]

First time it went to the Viper shop with a Viper tech he said there was water in 8 or 9 and 10. He looked inside and said all is well and it held compresion.

The car ran great for a while on a mixture of 75% 93 and 25% 100 octane.

the cylinders had WATER in them ? or antifreeze mixed with water ?

and why the need to run 100 octane ???

 

[Tabs1]

What codes did the car spit out?

 

[vincy]

the cylinders had WATER in them ? or antifreeze mixed with water ?

and why the need to run 100 octane ???

The Tech said water and not the white color he expected from antifreeze. He said it wasn't fuel, but the water thing doesn't make sense. The fuel tank was drained and refilled. No more "water" but still engine problems. I'm planning to get the coolant checked for hydrocarbons.

I'm under the impression the Mopar controller works with 100 octane but prefers race gas. I guess I was about 95 octane with the mixture I used. I ran the car down to about 93 octane and it didn'r run any better. Right not I'm about 30 % 100 octane and haven't driven the car much.

 

[vincy]

What codes did the car spit out?

I'll try to learn the codes. I think the fuse has something to do with the injectors but I'm not sure.

I really appreciate the input from all of you, we don't know what to do from here.

 

[plumcrazy]

what are you trying to do with the 100 octane ? whats the need ?

 

[vincy]

what are you trying to do with the 100 octane ? whats the need ?

I thought the Mopar controller needed higher than 93.

 

[Phun70]

Let me ask you a few questions here.
1. Are you saying that this fuse only blows when you get on it hard from 1 to 2?

2. Did your technician do a block test? (a chemical test to determine if there is a blown head gasket.)

3. Does the fuse ever just blow without doing anything?

4. What will happen if you just let the car sit and idle?

5. Is there ever a time that the car runs properly?

Help me with those questions and I will do my best to assist you with your problem. I am a Double Master Auto Tech, Advanced level Specialist, and A Viper Specialist. Let me know what codes also if possible. I will also need as much information about the vehicle as possible, mileage, modifications etc. How long have you had the vehicle? etc. Mark

 

[Phun70]

If you are correct about the position of the fuse, I checked my diagrams and from what you are saying, I believe that is fuse #11. Is this correct?

 

[fastmd]

93 octane it needs, no less. Get away from the 100 and try running a few tanks. The blown fuses don't make sense, my next step would be shipping it to a known Viper tuner.

 

[Phun70]

I am doubting that the fluid in the cylinders was water---Most likely it was fuel.

 

[Phun70]

The octane of the fuel doesn't matter much as long as it is at least 93. Most of the tunes I've seen require that much octane rating to function properly without knock. The higher octane won't hurt anything do don't obsess about that. (higher octane fuel is just more resistant to burning, and typically burns slower).

 

[Steve-Indy]

Sorry for your difficulties !!

Did your Viper have a cam position sensor replaced ?? (Could have been done as a RRT before you got it).

What are the numbers on your injectors?(interested in the second row of numbers just under the part number).

Was the fuse "ASD#1" ??

I would suggest that you ask your dealer for a printout of your Viper's service history to date.

 

[Phun70]

According to my research, if the fuse he is talking about is #11, then yes, that feeds the ASD#1 relay.
I'm wondering about the ASD itself, I've seen relays that will draw too much and blow the fuse.

 

[Viper Specialty]

If I recall, that fuse supplies the constant power to the PCM. The first place I would look is at the PCM, it sounds like it has something loose internally that is shorting it out under high G forces. Also possible would be a loose wire somewhere in the same circuit- and this could probably be replicated by fiddling with the wiring if that was the case.

Also reinforcing this theory is that there may have been fuel in the cylinders, this would likely be from the injectors going static open when the PCM/wiring is shorted out.

 

[vincy]

Sorry for your difficulties !!

Did your Viper have a cam position sensor replaced ?? (Could have been done as a RRT before you got it).

What are the numbers on your injectors?(interested in the second row of numbers just under the part number).

Was the fuse "ASD#1" ??


I would suggest that you ask your dealer for a printout of your Viper's service history to date.

The cam sensor was never checked as far as I know.


Yes its ASD1. I got the car new so I know most of its history, basically it has no history except this and the header install. Woodhouse put on Motons before I got the car. I don't know the injector numbers?

 

[vincy]

If I recall, that fuse supplies the constant power to the PCM. The first place I would look is at the PCM, it sounds like it has something loose internally that is shorting it out under high G forces. Also possible would be a loose wire somewhere in the same circuit- and this could probably be replicated by fiddling with the wiring if that was the case.

Also reinforcing this theory is that there may have been fuel in the cylinders, this would likely be from the injectors going static open when the PCM/wiring is shorted out.

Thers is one wierd thing. Sometimes when the fuse blows it goes into total limp mode, 5 mph to home. Other times it just runs ratty.

 

[vincy]

If I recall, that fuse supplies the constant power to the PCM. The first place I would look is at the PCM, it sounds like it has something loose internally that is shorting it out under high G forces. Also possible would be a loose wire somewhere in the same circuit- and this could probably be replicated by fiddling with the wiring if that was the case.

Also reinforcing this theory is that there may have been fuel in the cylinders, this would likely be from the injectors going static open when the PCM/wiring is shorted out.

It seems to blow the fuse when the wheels spin in second gear with maybe some wheel hop. Mark J suggested its a short but I don't know how to find this.

Thers is one wierd thing. Sometimes when the fuse blows it goes into total limp mode, 5 mph to home. Other times it just runs ratty.

 

[vincy]

According to my research, if the fuse he is talking about is #11, then yes, that feeds the ASD#1 relay.
I'm wondering about the ASD itself, I've seen relays that will draw too much and blow the fuse.

The fuse is ASD 1. Is there a relay that connects to this fuse?

 

[vincy]

If you are correct about the position of the fuse, I checked my diagrams and from what you are saying, I believe that is fuse #11. Is this correct?

Its ASD1. I don't see a #11.

 

[vincy]

Let me ask you a few questions here.
1. Are you saying that this fuse only blows when you get on it hard from 1 to 2?

2. Did your technician do a block test? (a chemical test to determine if there is a blown head gasket.)

3. Does the fuse ever just blow without doing anything?

4. What will happen if you just let the car sit and idle?

5. Is there ever a time that the car runs properly?

Help me with those questions and I will do my best to assist you with your problem. I am a Double Master Auto Tech, Advanced level Specialist, and A Viper Specialist. Let me know what codes also if possible. I will also need as much information about the vehicle as possible, mileage, modifications etc. How long have you had the vehicle? etc. Mark

1. It seems that it only blows on a hard shift.

2. I don't think the tech did a block test. What is that?

3. I don't know if it ever just blows. It may have happened because the car lost power at a time I didn't know about the fuse.

4. Nothing happens if you sit and the car and idle.

5. As I think back the car has run bad for a long time. What I notices was a lot of backfiring that kept getting worse and worse. It wasn't backfiring when it was running good. The car always had a burning smell when running, but I though that may be the exhause near the window. Someone following me said the car smelled bad. It has been this way since new. Except for a few times when it was running great it hasn't felt as strong as I expected.

I got the car new from Woodhouse. Its a 2008/ It has about 5000 miles. The only mods are Motons, long tube headers and the Mopar computer.


Thanks for your help.

 

[vincy]

If I recall, that fuse supplies the constant power to the PCM. The first place I would look is at the PCM, it sounds like it has something loose internally that is shorting it out under high G forces. Also possible would be a loose wire somewhere in the same circuit- and this could probably be replicated by fiddling with the wiring if that was the case.

Also reinforcing this theory is that there may have been fuel in the cylinders, this would likely be from the injectors going static open when the PCM/wiring is shorted out.

We suspected the PCM. Mark J sent us a second one and it behaves the same way.

 

[VAViper]

Have you tried swaping back to the stock PCM? If all is well with the stock PCM, you'll know it's the mopar controler. Just a thought..

 

[Phun70]

1. It seems that it only blows on a hard shift.

2. I don't think the tech did a block test. What is that?

3. I don't know if it ever just blows. It may have happened because the car lost power at a time I didn't know about the fuse.

4. Nothing happens if you sit and the car and idle.

5. As I think back the car has run bad for a long time. What I notices was a lot of backfiring that kept getting worse and worse. It wasn't backfiring when it was running good. The car always had a burning smell when running, but I though that may be the exhause near the window. Someone following me said the car smelled bad. It has been this way since new. Except for a few times when it was running great it hasn't felt as strong as I expected.

I got the car new from Woodhouse. Its a 2008/ It has about 5000 miles. The only mods are Motons, long tube headers and the Mopar computer.


Thanks for your help.

1. It may be that some wiring is being stressed or pinched when the engine and transmission move due to torque output, if this is the case, you might be able to duplicate the concern by pulling and twisting all the wiring harnesses near the engine and transmission to see if the fuse will blow again. If so, localize the area that caused it to blow the fuse when pulled on and remove the wiring overwrap--check inside for chafed or pinched wires.


2. A block test is a chemical test that is done at the coolant fill. In your case it would be the surge tank. It is a test that checks for a blown head gasket by watching for a chemical reaction.

3. The fact that nothing happens when the car sits and idles makes me think that there is NOT a blown head gasket, because the engine would most likely overheat if there was, and you just let it sit and run. Additionally, if there were a blown head gasket allowing fluid in to the cylinders, then it would have to be adjacent cylinders and not one on each side of the engine. As I said before, I think that you had fuel in the cylinder due to leaking injectors, or the computer was commanding the injectors to hold open for some reason.

4. I would recommend replacing the ASD#1 relay, (AUTO SHUTDOWN RELAY) This relay feeds power to the PCM, AC compressor clutch relay, the low speed fan relay, the mass air sensor, and the leak detection pump. also, the fuse is another power feed to part of the computer (PCM) and you are losing power there when the fuse blows. So, when the fuse finally blows, there are two of the power feeds to the PCM (powertrain control module) that aren't there anymore.

 

[Steve-Indy]

...and, the proposed short could be in the harness to the PCM.

Were it mine, I'd be loading it up for a road trip...to Tator, Sessions, or Woodhouse, etc.

 

[Phun70]

I would have to agree.

 

[Phun70]

Oh, I forgot---DO NOT UNDER ANY CIRCUMSTANCES PUT A LARGER FUSE INTO THAT SLOT!!!!! (OR ANY OTHER SLOT FOR THAT MATTER!) ALWAYS USE THE PROPER RATED FUSE AS CALLED FOR IN THE OWNERS/SERVICE MANUAL. (You know that something is broken when you let the magic smoke out!

 

[vincy]

...and, the proposed short could be in the harness to the PCM.

Were it mine, I'd be loading it up for a road trip...to Tator, Sessions, or Woodhouse, etc.

I was thinkg that but its so hard to find I thought it could be a wasted trip.

 

[vincy]

1. It may be that some wiring is being stressed or pinched when the engine and transmission move due to torque output, if this is the case, you might be able to duplicate the concern by pulling and twisting all the wiring harnesses near the engine and transmission to see if the fuse will blow again. If so, localize the area that caused it to blow the fuse when pulled on and remove the wiring overwrap--check inside for chafed or pinched wires.


2. A block test is a chemical test that is done at the coolant fill. In your case it would be the surge tank. It is a test that checks for a blown head gasket by watching for a chemical reaction.

3. The fact that nothing happens when the car sits and idles makes me think that there is NOT a blown head gasket, because the engine would most likely overheat if there was, and you just let it sit and run. Additionally, if there were a blown head gasket allowing fluid in to the cylinders, then it would have to be adjacent cylinders and not one on each side of the engine. As I said before, I think that you had fuel in the cylinder due to leaking injectors, or the computer was commanding the injectors to hold open for some reason.

4. I would recommend replacing the ASD#1 relay, (AUTO SHUTDOWN RELAY) This relay feeds power to the PCM, AC compressor clutch relay, the low speed fan relay, the mass air sensor, and the leak detection pump. also, the fuse is another power feed to part of the computer (PCM) and you are losing power there when the fuse blows. So, when the fuse finally blows, there are two of the power feeds to the PCM (powertrain control module) that aren't there anymore.

Maybe 4 explains the different behavior, sometimes just runs ratty and other times goes into limp mode.


In 2 do mean a chemical reaction to check for hydrocarbons?

 

[vincy]

Oh, I forgot---DO NOT UNDER ANY CIRCUMSTANCES PUT A LARGER FUSE INTO THAT SLOT!!!!! (OR ANY OTHER SLOT FOR THAT MATTER!) ALWAYS USE THE PROPER RATED FUSE AS CALLED FOR IN THE OWNERS/SERVICE MANUAL. (You know that something is broken when you let the magic smoke out!

The way I feel now is not to use a bigger fuse, just to put a wire across the 2 connections.

Just kidding, but this is frustrating.