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Tony
Dodge Dakota
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2/25/2004
17:34:45
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 Subject: Why does my dakota sound like a shotgun?
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I have a 91 dakota V8. This happens both when I rev-up my engin or when im driveing and im in the high rpm's and i let off. On the de-rev my exaust pops and crackles preaty loud, but just today when i was driveing home i was turning about 4500rpm and when i let off it sounded like someone had just shot a shotgun.I have a flowmaster muffler with no cat. Can you help me out with this one im stumped. Thanks
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piston
Gen II
2/25/2004
17:42:10
|  RE: Why does my dakota sound like a shotgun?
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probably running rich, and with low back pressure that loud shotgun sounding noise was a small explosion of unbunrt gas in the tail pipe, or your timing is off and it was a back fire but most likely its just running rich.
Keep The Shiny Side Up
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Kowalski
Dodge Dakota
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2/25/2004
18:23:16
|  RE: Why does my dakota sound like a shotgun?
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Read your plugs. I think you'll find you're running a little lean from the exhaust changes.
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WipLash
R/T
2/25/2004
18:47:06
| RE: Why does my dakota sound like a shotgun?
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Sounds like you have an exhaust leak. A very small hole in the y-pipe, manifold, blown eaxhaust manifold gasket, or just rotted tubing (91's didn't have stainless exhaust) will allow air to come in. What happens is when you let off the gas the throttle blades close. The engine is still spinning at a high RPM. There is the remaining unburned gasses still in the exhaust trying to escape. For a split second your exhaust goes into a state of vacuum. If you have any exhaust leaks close to the exhaust manifold fresh air will get sucked into the exhaust by the vacuum. If there is any unburned gas in your exhaust when the fresh oxygenated air enters you will reignite the exhaust and cause an explosion.
We actually did this on purpose to our cars when I was a teenager. We would drill a small 1/8" hole upstream in the Y-pipe just so the exhaust would fire off evrytime we downshifted. That's OldSchool stuff.
Another thing that will complicate this is a bad spark plug. This will allow more unburned gasses to enter the exhaust. If there is any leak in the exhaust system it will explode when you let off the gas and coast. Especially if you have a standard and you compression brake from high RPM's.
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Timberwolf
GenIII
2/26/2004
08:50:14
| RE: Why does my dakota sound like a shotgun?
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In simplified terms, what everyone is saying is get a tune up. That will take care of your problem. If you don't, you may eventually blow a hole in your muffler.
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Mark
Forum Moderator
2/26/2004
08:53:43
| RE: Why does my dakota sound like a shotgun?
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I have had the same thing since I got my truck. It usually does it when i'm goign down a hill and drag it in a lower gear. I have an automatic. Snap Crackle Pop. Its normal from what I see. I have had a new exhaust and numerous tuneups. Runs fine.
-Mark Hryckiewicz
1993 Sport RC SB 5.2L Auto
Mark.DodgeDakotas.com
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Timberwolf
GenIII
2/26/2004
09:56:16
| RE: Why does my dakota sound like a shotgun?
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Mark - Anytime you let off the accel quickly at high RPM, you will get some of that because of unburned gas in the pipes,even if your engine is in perfect tune. This is amplified if you have a free-flowing exhaust. This is normal(and sounds kind of cool), however, he said his sounded like a shotgun blast. That's a good old fashioned backfire and is a sure sign of an engine in need of a tuneup.
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01Motorsport
Dodge Dakota
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2/26/2004
10:05:00
|  RE: Why does my dakota sound like a shotgun?
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Tony, I noticed you said "no cat". Catalytic converters absorb a lot of sound waves. Tune ups are good. After plugs/timing/air fuel check, it still happens, don't worry too much. A sidebar here; I believe Chrysler went to stainless exhaust in 1985. I pinstriped BMW cars for a local dealer in the 80's. A salesman proudly told me 1987 that the Bimmers now had stainless steel exhaust! I told him, "Yeah, my '85 Dodge mini van does, too!". You could see the question mark planted on his face as he said, "Dodge???", and walked away. Sorry, WipLash, you just tripped a memory...
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DSW
Dodge Dakota
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2/26/2004
12:14:00
| RE: Why does my dakota sound like a shotgun?
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Talk about tripping a memory, back in high school I had a 72 pickup with dual side exhaust. For fun we would get it up to about 30-40 mph, cut the ignition and pump the heck out of the carb to load the exhaust with raw fuel. Hit the ignition and viola, instant flame thrower and shotgun blast sound.
Well, I should say it was fun until we caught the attention of the local PD. It wasn't too much fun trying to explain why there were 5 foot flames shooting out from the sides of the truck. LOL
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WipLash
R/T
2/26/2004
13:42:15
| RE: Why does my dakota sound like a shotgun?
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O1motor,
I don't know about minivans, but the Dakota came out with stainless in 1993. I remember it quite well because I had both. It was a big deal back then to upgrade to stainless. Borla was coming out with a stainless system for just about everything. I was waiting patiently for Borla to offer a system for my 92. By the time Borla offered a cat-back for the 92 the 93's were already out and they came with stainless. I was tired of the 92 4x4 by that time anyway so I traded my 92 in for an almost new 93 in Dec 93.
That's why you see so much custom exhaust on Chevy's and Fords. They have no choice. After 5 years their sh!t falls off. It wasn't until like 97 or 98 befor Chevy started putting stainless on their trucks. I know the 96 Chevys didn't have stainless because my best friend has a 96 Silverado and all his sh!t rotted off 2 years ago. He had a custom exhaust made for the truck 2 years ago and now it is rotting off. BUY DODGE!!
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Timberwolf
GenIII
2/26/2004
14:05:38
| RE: Why does my dakota sound like a shotgun?
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Back in high school I knew a guy who had an old black chevy stepside with stacks. He rigged spark plugs in the pipes and used to drive by and shoot flames out the top. That was pretty cool to see at night.
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Kowalski
Dodge Dakota
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2/26/2004
16:09:27
|  RE: Why does my dakota sound like a shotgun?
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I din't say anything about a tune up. I've seen this happen on other vehicles that were running lean due to exhaust mods similar to what he has done. Cackle or backfire when downshifting or getting off the gas.
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Tony
Dodge Dakota
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2/26/2004
18:15:30
| RE: Why does my dakota sound like a shotgun?
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It turns out to be the air pump solinoid. I talked to a few people and they said that it tends to wear out and stick open. I disconected the air line running to the exahaust fired it up no crackling.What hapens is pockets of air build up and when the exhaust presure is let off it escapes with a loud bang.
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WipLash
R/T
2/26/2004
22:58:36
| RE: Why does my dakota sound like a shotgun?
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Message:
Well, like I said you had an exhaust leak. With the valve for the air injection stuck open, it was just like having a hole in the manifold.
I forgot the 91's had that crap on there. Rip those manifolds off and stick a set of 92 manifolds on there.
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