What is wrong with this srt4?

My friend has a 04 srt4, around 20,000 miles on it, the only thing done to it is an aftermarket downpipe and intake. For some reason just in 3rd gear if he is on it, it seems like it backfires and looses all boost and then boost up again after it goes down. It doesn't do it at a certain rpm, just does it randomly. Sometimes it does it and sometimes it doesn't do it at all. The thing that is getting me is that it only does it in 3rd gear and doesn't do it all the time. Any idea's about what might be wrong with it?

Gap the plugs down to around .30 and see if it still does it

Ok, I'll tell him to do so, but what is the reason why his car is doing this?

his plugs are fouled, i bet they are the originals arnt they. the SRT plugs need to be changed every 10,000-15,000 because of how rich the car runs. he is getting spark blow out. too much cylinder pressure, too big of a plug gap, and not enough spark energy means that the sparkplug doest fire. this is the bog that he feels. have him get ahold of his local speed shop and get a set of NGK 4306 sparkplugs. gap them to .035-.040 (i am running more boost and more mods and have mine gapped to .038). the car will run awesome with that setup

I just got my NGK's:p I'll be putting them on tomorrow. I hope they are worth the 9 dollars a plug. What gapping do you suggest for 18.5-19 psi? I was thinking 40 but not too sure.

i dont see anything in your mod list that will allow you to run more than 18psi (spiked) and fall to 15psi. if you spike over 18, your car will be SLOWER than if it spikes 18. timing makes more power than boost. with that much boost, if the mods can accomidate, gap to around 35, i am assuming they are the iridiums at that price, if so then you can get away with 38 or so, but its not worht going more

Me and him got some new plugs and gapped them to what u said and still just in 3rd gear it does it. But also if he is flat on it through every gear it doesn't do it, it only happens if he shifts reg. in 1st and 2nd then if he punches it in 3rd it is when it does that. Anymore idea's?

Have you tried resetting the pcm?

how are your wires. look at the cyl4 (drivers side). look at the boot, is it white or discolored at all? buy a set of MSD or CRANE wires, that should help as well. also make sure he's running good gas (91 octane or better)

Actually, the SRT4 reqires 92 or better octane rating. This might be a long shot but I think he may have a problem with the TPS harness. Mine started with wierd idling then bogging while driving. So, I did the check by wiggling the TPS harness then the engine bucked and threw and engine code. I had DCX dealer repair the harness and it's been good to go from then.

if you want to be technical...dodge recommends 93. thats what it says in my 03 owners manual . however, most of us dont have access to anything more than 91, so thats what we run. race gas is too expensive.

.35 gap ? .40-.45 I would say. Also the owner manual says 91 octain.

.04-.045 is too much for anything more than stock boost levels, and even then it wont last.

i double checked my owners maual yesterday, and just what i thought, it says 93...but this is one of the first srt's off the production line. it still says run 10w30 oil instead of the 5w30 like most others.

.04-.045 is too much for anything more than stock boost levels, and even then it wont last.

i double checked my owners maual yesterday, and just what i thought, it says 93...but this is one of the first srt's off the production line. it still says run 10w30 oil instead of the 5w30 like most others.


So strange they would change the octain rating in the later years. Any ideas why? I only use 93 anyways but I'm just curiouse.

in 2003 the srt was sold only in cali and florida. so they recommended the good fuel because its available...well in florida atleast. after that, they realised that 93 wasnt available everywhere so they got smart...im totally guessing, i dont know the real answer

in 2003 the srt was sold only in cali and florida. so they recommended the good fuel because its available...well in florida atleast. after that, they realised that 93 wasnt available everywhere so they got smart...im totally guessing, i dont know the real answer
no, the '03's were available everywhere.

check again...they were sold from DCX in only florida and cali...other dealers bought them from those two states. check the archives at srtforums and you'll see. also, that is why the large number of older cars are in both states. heck in the beginning there were only a couple in texas, srtgurl, then the cali guys and the florida guys

Shouldn't this be a warranty job?

check again...they were sold from DCX in only florida and cali...other dealers bought them from those two states. check the archives at srtforums and you'll see. also, that is why the large number of older cars are in both states. heck in the beginning there were only a couple in texas, srtgurl, then the cali guys and the florida guys
From what my dealerships tell me (I'm an aftermarket shop owner that sells/installs stuff at dealerships) they said DCX did ship the '03's in the warmer climate areas first because it was still winter in the midwest. They ALL told me they don't do dealer trades from Florida dealers (we're in Ohio) because of the distance and each only got one 2003 each. That then changed for 04 and 05.

As far as Octane ratings vs. what the car states it needs to run, I'll have to check to see what my manual actually says (mine's an '04). I'll try to remember what it acutally says. I was thinking 92 but maybe it says 93??? It doesn't matter because I have 2 stations that have 94 which is what I run. Also, I was thinking that you can find 93 octane in every state??? Again not sure. I know all states from Ohio to Florida and to the Carolina's do.

First off, as far as the limited availibility of fuel over 91 octane, here in Michigan, 92 and 93 octane can be found practically everywhere. Sunoco's here sell 92 and 94 octane standard, and there are two Sunuco's within 10 miles of me (one of them in the middle of nowhere) that sell that way-over-the-top 104 and 110, and charge an a$$load for it.

Second, there are SRT4's all over up here. In fact, in the fall of '04, the Adrian Dodge dealership here had so many '04s left over on their lot, they discounted them new and offloaded the last of them to the public for $16,900 after discounts. I was pissed I couldn't get one... I just bought my '04 SXT less than six months before that (for $10k).

Also as far as car sales, I learned some things I never knew. Living in Michigan (with only limited months of summer-like weather) you wouldn't expect to see a bunch of high-$ exotics driving around... but my dealership here in Monroe sells more Vipers than any other in the country. Many of them get sold here, but I also found out that many of them are only BOUGHT here, and shipped across the country to the customer. This is because being downstate from Detroit, we get deals like crazy from dealers here on cars that many dealerships (say in Florida or Cali) don't offer. So it behooves some people to purchase a car from a Detroit dealership for $5000 less, and pay the measly $500 charge to ship it out to their local dealer across the country.

Okay, enough rambling... just thought I would add the info.

Here in Nebraska:D 93 octane is hard to find. There is only one place that I know of, but it also has 10% ethanol in it. So it's basically like 91.

hmm... I think here in Michigan most of ours are all 10% ethanol, which isn't too bad. I filled up with 87 in Iowa one time at a BP station, and when I just got done I looked at the pump and saw this TINY little sticker that said "100% Ethanol for a cleaner Iowa!" Damn. Needless to say, my car threw me a CEL before I got to Michigan lol.

Here in Nebraska:D 93 octane is hard to find. There is only one place that I know of, but it also has 10% ethanol in it. So it's basically like 91.
Just because it has an ethanol blend doesn't mean the ethanol waters down the mixture. There is a place up next to the dragstrip that sells 107 octane race gas with ethanol.

Just because it has an ethanol blend doesn't mean the ethanol waters down the mixture. There is a place up next to the dragstrip that sells 107 octane race gas with ethanol.

...word.

Just because it has an ethanol blend doesn't mean the ethanol waters down the mixture. There is a place up next to the dragstrip that sells 107 octane race gas with ethanol.

Ethanol is shit for any sort of performance.

If you follow the NHRA, you'll see many of the teams run straight ethanol.

If you follow the NHRA, you'll see many of the teams run straight ethanol.

And they also have engine specifically made for alcohol burning as well.

We run engines made to utilise gasoline, not alcohol.

There's plenty of additives to make ethanol run just fine in regular vehicles. This reminds me of when synthetic oils first came out. Everyone was saying how bad they'd be for your engine especially if it was an engine with some age on it.

Mazy I ask what these additives are that counteract the downfalls of alcohol in a gasoline burning engine?

Personally, I don't know the actual names of these additives since I am not a chemist nor a mechanic. The problem is when you have a mechanic who says not to use E-blended or 100% fuel simply does not have correct information—particularly since every major automaker in the world approves the use of blended ethanol under warranty. Fuel formulation and fuel quality have changed dramatically over the years, and many auto mechanics simply don’t have current information or knowledge of these changes and how they affect engine performance. The result: When a problem appears to be fuel related, some mechanics will immediately ask if E-10 Unleaded has been used—and if so, blame ethanol for the problem. In some states, E-10 Unleaded advocates have offered a substantial reward to any customer who can document damage from E-10 Unleaded to his or her car—and so far, no one has ever collected. Most problems happen with Dinofuels that have that waxy additive. Those usually gum up fuel injectors and is the number one result in injector failure.

Here's some things Ethanol does that's good...
Additional octane: The ethanol in E-10 Unleaded adds two to three points of octane to ordinary gasoline, helping improve engine performance. Most people think E-10 is used to "water down" the gas but it mearly a way to boost the octane!
Cleaner fuel injectors: Ethanol helps prevent the build-up of power-robbing deposits in fuel injection systems. This is used to burn the wax buildup from Dinofuels.
A gas line antifreeze: Ethanol suspends moisture in the fuel systems, eliminating the need for gas tank additives in cold weather. Ever look at what Drigas is????
Cleaner air: Ethanol reduces toxic emissions in engine exhaust, helping keep America’s air cleaner.

Hey,
Hmmm, sometimes you run into waste gate issues if you reduce backpressure and/or intake restrictions. If you peg the allowed boost pressure you will feel the wastegate opening as a 'bog' or power drop. Anyone who has ever driven a turbo hard knows that the opening and then closing and then rebuilding of the boost pressure causes a turbo lag and a power loss. If the bog is 1-5 seconds and then powers seems to be restored, this could be the problem. Maybe as a test only, you could disable the waste gate and see if it is still doing it. SRT's run pretty rich anyway so one run in 3rd to see if the problem is now gone or not should safe.

Swede1

I bet he was going wot before 3k rpms because he said he lightly shifted into 1st and 2nd...so since he was below 3k the turbo surged, caused the car to backfire and buck and feel like shit, number one problem with newer srt owners.

Would it hurt the car if you ran too high of an octane fuel cus i have access to 109 octane race fuel?

No point in using it seeing you won't see any real difference for the price of it.

And in addition, you have to have the supporting mods to get any real power out of it.