Engine pops and bucks above 3000rpm

[kblake905]

It was suggested I repost this message here, sorry for those that have already read it elsewhere.
I just bought a 2004 SRT10 Convertible from Ebay, drove it home approx 1000 miles. Car has 8000 miles on it now. The car averaged close to 25mpg driving it home. Always filled it with 91or higher octane. Just spent the day at the local Dodge dealer and they are stumped? Car will not pull past 3000 rpm without coughing and bucking, there is a hint of oil burning smell after these episodes. Fuel pressure tested 60 psi. Computer was updated with the latest software upgrade. Oil and filter changed. Dealer is suggesting camshaft may have slipped a gear, which would be a major repair for me after just buying. Sorry for being long winded, hoping someone can help.
Also it seems curious that my trip odometer keeps resetting to zero by itself, and the radio loses its preset memory???
Thanks

 

[ulllose]

Did you buy it from a dealer or private owner????

If private owner give them a call and ask some more history about the car?

Good luck with that one, what a bummer after all that money spent and time getting the car

Did it pull past 3k rpm's on the way home?? If so when did it start

 

[britospeed]

Ask the dealer to data log all of the engine sensor outputs while the car is running. Paying close attention to the crank and cam position sensor output wave form. Does the car rev fine without a load? Another simple thing to have them check is the TPS sensor.

 

[dave6666]

Plugged cats? Would maybe seem a little strange on an 8K car, but my 0.02 for the day.

 

[mjorgensen Woodhouse]

Plugged cats? Would maybe seem a little strange on an 8K car, but my 0.02 for the day.

We have seen it before and depending on the actual history of the car you never know why but it can happen.

 

[Shandon]

Check the cats for possibly being plugged or other (Like Dave said). You also mention electrical issues? Watch your volt meter when driving over 3k and see if its fluctuating or moving around? Loss of voltage or lack would cause issues too.

 

[kwiksilver]

this is where I would go first. Low voltage is what is probably what is causing your problem with the trip odo. and your radio presets. Your ignition system probably needs higher current to fire at higher rpm's.

 

[kblake905]

Did you buy it from a dealer or private owner????

If private owner give them a call and ask some more history about the car?

Good luck with that one, what a bummer after all that money spent and time getting the car

Did it pull past 3k rpm's on the way home?? If so when did it start

It was bought on a private sale, owner is denying anything wrong with car when he gave it to me. It is snowing here today, so the car is staying in the garage! Engine was breaking down with no load? I will also have the battery tested. Not sure if the computer monitored that when it was at the dealer? I will ask them to data log the car, next time. The computer was in the car and hooked up when he took it out for a test drive, but I am not sure if he recorded any readings. Thanks again for the ideas.

 

[plumcrazy]

check the cats quick..

start the car, put hand behind the exhaust and tell us how far away you can feel the pressure. then go to the other side and do the same and tell us if there is a difference in sides. (telling us 1 cat is clogged)

 

[bluesrt]

It was suggested I repost this message here, sorry for those that have already read it elsewhere.
I just bought a 2004 SRT10 Convertible from Ebay, drove it home approx 1000 miles. Car has 8000 miles on it now. The car averaged close to 25mpg driving it home. Always filled it with 91or higher octane. Just spent the day at the local Dodge dealer and they are stumped? Car will not pull past 3000 rpm without coughing and bucking, there is a hint of oil burning smell after these episodes. Fuel pressure tested 60 psi. Computer was updated with the latest software upgrade. Oil and filter changed. Dealer is suggesting camshaft may have slipped a gear, which would be a major repair for me after just buying. Sorry for being long winded, hoping someone can help.
Also it seems curious that my trip odometer keeps resetting to zero by itself, and the radio loses its preset memory???
Thanks

you may have a alternater not charging at times,and or a battery shorting,not accepting a charge,a shorted battery can be fine at a small load,and freak out at a large load,wich 3k would be a large load,just another suggestion to help-

 

[mike & juli]

kblake: Welcome and hope with all the expert advice you're getting, you'll resolve your problem. In the meantime, private message your VIN# to the moderators to UPGRADE you to VIPER OWNER (lee00blacksilvergts, kcobean). If not mentioned already, call our Viper Wizard/Chuck Tator 1-914-763-3136. CONGRATS on your 2004 Vert!~! ~juli

 

[kblake905]

check the cats quick..

start the car, put hand behind the exhaust and tell us how far away you can feel the pressure. then go to the other side and do the same and tell us if there is a difference in sides. (telling us 1 cat is clogged)

no discernable difference in exhaust pressure??

 

[kblake905]

Thanks to all who replied, I gave up on the dealer trying to figure out this problem. A local mechanic was reccommended to me, and he figured out in a half hour that a plugged cat was my problem, he is going to replace that with an aftermarket one, and then we will go from there, ie: he is not sure why it plugged in the first place?

 

[Martin]

Thanks to all who replied, I gave up on the dealer trying to figure out this problem. A local mechanic was reccommended to me, and he figured out in a half hour that a plugged cat was my problem, he is going to replace that with an aftermarket one, and then we will go from there, ie: he is not sure why it plugged in the first place?

Before just replacing one cat with an aftermarket one, do some research here on the best ones that people have installed with good results. Mark at Woodhouse and JonB at Parts Rack would be good resources to find out what your options are. As long as it has to be replaced, you may as well replace BOTH SIDES with a set that is an upgrade and gives you an easy upgrade path later on if you want to add to the exhaust system.

 

[SteveBCloud9]

I'd do new plugs too... you'd be surprised how new plugs will even out a Viper engine even with 8-10k miles on it.

 

[dave6666]

I'd replace both sides regardless of whether you upgrade to hi flows or not. Who's to say the other one is flowing 100%?

 

[kblake905]

I'd do new plugs too... you'd be surprised how new plugs will even out a Viper engine even with 8-10k miles on it.

Thanks, I am having new plugs installed also.

 

[kblake905]

I'd replace both sides regardless of whether you upgrade to hi flows or not. Who's to say the other one is flowing 100%?

The mechanic has one of those snake cameras that he was able to poke into the co sensor opening and it looked fine. I also have to replace the rear tires and the front wheel bearings before I can certify it; which I need to get the plates here in Ontario, these extra bills on top of the purchase price don't impress the wife much!!!

 

[eucharistos]

I also have to replace the rear tires and the front wheel bearings before I can certify it; which I need to get the plates here in Ontario, these extra bills on top of the purchase price don't impress the wife much!!!

you probably know already, but just in case, check here for your tires 1st (ask jonb for your options)

PartsRack.com - Home Phone: 360-837-3937

 

[PaViper]

May be a really stupid question, but how old is the battery, is it original

 

[JonB]

Id love to be worthy to provide cats but:

I am concerned that the symptoms you describe, mainly the "Self Reset" of electricals, has ZERO to do with the cat, and everything to do with the computers/ignition. The cats being plugged are a SYMPTOM, not a cause.....

- The reason your cats are likely BOTH deteriorated is the very 3000+ RPM bucking and incomplete burn you clearly cite, and can reporduce! Unburned fuel destroys cats. And smells as you describe.

- The GROUND may be bad and the vibrations above 3000 RPM make it worse. This also explains the self-reset, the NO CELs, and the radio memory clearing.

YOU HAVE AN ELECTRICAL / CRANK SENSOR...03-04 issue / COMPUTER ISSUE.

It may be as simple as a BAD BATTERY, or BAD BATTERY GROUND, or BAD ALTERNATOR (not likely)

But if you replace the cats NOW, it will NOT fix the CAUSES, and you'll ruin the new cats too. Trust me on this!

It amuses me that the dealer changed the oil as a possible fix...I had an old girlfriend who thought like this, changed the oil at every problem!

 

[mopower]

The front cat on the right side of my '06 had come apart on mine at 13,900 miles and stopped up the downstream one.. I remedied the problem with the 3 inch race exhaust from Mopar. Mine had the same symptom.

 

[Chuck 98 RT/10]

If you listed your location in your profile a member might be able to recommend a good dealer or Viper specialist in your area. But since you didn't I will just recommend you take it to Tator or Woodhouse.

 

[Joseph Dell]

...I had an old girlfriend who thought like this, changed the oil at every problem!

I used to have the opposite issue... but I'd change the girlfriend at every problem.

Listen to JonB... find the root cause of the problem, else you'll be back at square-1 sooner than you'd like.

Is it possible to buy a used <anything> without inheriting someone else's problem???

 

[99 R/T 10]

Is it possible to buy a used <anything> without inheriting someone else's problem???

The answer to that is no..................... what do I win?

 

[kblake905]

All is well with my new viper now, once again thanks for all the suggestions. I have replaced the offending cat, added new plugs and front wheel bearings, front end alignment and rear tires. Now I have got to learn how to drive it, its scary fast after driving a minivan for the past 20 years.
My son has signed me up for the SRT Track experience in Virginia in July

 

[eucharistos]

All is well with my new viper now

congrats and

..... its scary fast after driving a minivan for the past 20 years.

yeah baby