25 replies to this topic

[Bailman]

Have had a tailpipe backfire and read that the bad MAP Sensor is bad so I replaced MAP and it still has tailpipe backfire though the car feels better. It happens when giving it a nice amount of pedal or @WOT. It doesn't matter if I have it in 3 or 4th gear or (D)rive. What else should I look into doing/replacing to stop this?

[Mopar408]

Any codes?

[Hemituner]

Sounds like you may have broken a valve spring. I suggest getting the valve covers off to take a look.
Hope this helps
AJ

[Bailman]

 No codes. OK will do on the covers, Aj

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[Hemi31]

Was the any other noise? Broken or weak spring is a possibility and so is a bent pushrod.

[Goehner]

The only time I had backfire on my car was when the #1 plugs were crushed, broken ring lands on the factory 392. Good luck finding the issue.

[THE PHANTOM]

Was this a constant thing bailman. I had this happen to me twice after I got my car back on a new build.. I thought it was because it was really cold outside leading to a rich condition in the tune due to my car being tuned in the 95+ Florida heat. It did it when it was really cold in December twice one day and then another cool evening around April when I was driving it to the track. It never did it under load at the track. I have yet to put the valve covers. May get my mechanic to do so. I think also my plugs may have been gapped to much as well. I think I did a plug change after that. I haven’t had it happen since but after this post I am a little concerned on the internals. Could be nothing my car is far from stock but who knows?

[Bailman]

Was the any other noise? Broken or weak spring is a possibility and so is a bent pushrod.

No other noise, E. This wasn't a one time thing. Its anytime I get into it for a HWY pass or HWY Shits/Giggles WOT. No lights/codes... not even general misfire. MPG is down historically. I know we spoke about changing out springs way back when. Does someone know which springs I need for the MDS I still run? I would order some new ones if I could remember.

The only time I had backfire on my car was when the #1 plugs were crushed, broken ring lands on the factory 392. Good luck finding the issue.

Thx, Dude. I'll let ya know what the outcome is/was.

Was this a constant thing bailman. I had this happen to me twice after I got my car back on a new build.. I thought it was because it was really cold outside leading to a rich condition in the tune due to my car being tuned in the 95+ Florida heat. It did it when it was really cold in December twice one day and then another cool evening around April when I was driving it to the track. It never did it under load at the track. I have yet to put the valve covers. May get my mechanic to do so. I think also my plugs may have been gapped to much as well. I think I did a plug change after that. I haven’t had it happen since but after this post I am a little concerned on the internals. Could be nothing my car is far from stock but who knows?

Yeah, Bish. This is a reoccurring thing but now I think about it it might not be 100% of the time. Maybe coil packs or wires but the no codes has me stumped with what has been happening.

[Knownman]

Curious about this discussion.

I get a back fire occasionally. Only time I notice is when in 2nd gear and I get off the throttle. Sometimes I hear it backfire.

I don't notice anything during Wot boost or normal?

What do you guys think?

[Hemi31]

Brian how old are the plugs?

[Knownman]

Erik,

Are you asking me about the plugs?.

If so they're copper 4306's with 7k or so miles.

Only happens when I get out of the gas and stay in gear and the car engine brakes.

[Bailman]

Brian how old are the plugs?

I changed them this Late Spring. What freak'n spring do I need to get and where is "the place" to get them that will allow MDS Activity and go with the parts in me Sig? <Haha> MDS Activity. My brain is shot and needs some help in recollecting.

[Hemi31]

MDS has nothing to do with the springs. Its all.in the lifters. As long as the cam has lift low enough for the lifter to actuate MDS works. Since you have the FRI SS heads you have the PAC 1518 springs. Josh should be able to get them. If not call me and I will get them.

[Knownman]

Guess you aren't asking me

 

[asianANDY]

Bailman,

 

I'm having this issue too...the car backfires half the time when I hold it in gear then got wot or give it a nice amount of gas. When this occurs,  feels like it hits a brick wall. The car goes limp, I remove my foot from the gas pedal and a second later...everything is back to normal. I'm going to follow this thread closely to see what solves your issue and I might try it myself.

[Bailman]

MDS has nothing to do with the springs. Its all.in the lifters. As long as the cam has lift low enough for the lifter to actuate MDS works. Since you have the FRI SS heads you have the PAC 1518 springs. Josh should be able to get them. If not call me and I will get them.

Thanks for the info. Josh should be on his Honeymoon so perhaps you'd be a better vendor. Tony gonna do the work so let me know the $$$ and give me your # so I can get these ASAP. One last thing, Bro. What Iridium's should I get? B/c I cannot keep changing plugs every season which these coppers only seem to be lasting.  

[Bailman]

A update to all of the tailpipe backfire issues. It has apparently cleared up. After more days with the new MAP Sensor installed I have yet to see any of the problems I was experiencing before and just after replacement. Its a cheap and fast way of seeing if that is causing the problem. Hope this helps.

[TA340]

Good to know it was a cheap and easy fix. Thanks for updating. It is always good to learn from others positive experiences.

[Goehner]

Glad you got it worked out.

[1FST4DR]

Erik,

Are you asking me about the plugs?.

If so they're copper 4306's with 7k or so miles.

Only happens when I get out of the gas and stay in gear and the car engine brakes.

Well Im not Erik but one thing I notice is if you are boosted you are running the wrong plug.  You should be running 1 step colder   If you are not boosted then you are fine with that plug   I just didn't remember what your Mod list was..

Thanks for the info. Josh should be on his Honeymoon so perhaps you'd be a better vendor. Tony gonna do the work so let me know the $$$ and give me your # so I can get these ASAP. One last thing, Bro. What Iridium's should I get? B/c I cannot keep changing plugs every season which these coppers only seem to be lasting.

 

I 'think' you would run a 2314 ngk same heat range as a 6.1  which will be one step colder.   Or a 2315 will be 2 step colder...