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99BarneyRT
03-12-2008, 11:54 AM
Got a problem guys, like some help if I can get it :). For those that don't know, last year I revamped the upper end of the motor. Let me do a little back track to show everyone knows where I'm at.

In my signature was my last dyno session. This was with 52mm TB, .020 block, stage 2 port RT heads, PHAT cam, 1.7RR, M1 2 bbl, Mopar headers, B&G flash. Truck ran fine, but as we all get bitten, I wanted more HP and closer to 400RHP.

Since then, I've up'd the port on the heads to Stage 3, went to 4 bbl M1, LT headers, and single blade 1000 CFM TB. Basically a rebuilt upper end on the motor.

Since the rebuild I have been chasing problem after problem after problem. I have worked them all out but one. The truck currently has 2 issues...a constnt #7 misfire and surging at OD. I have changed the wires, plugs, cap/rotor. Of course, doesn't mean I didn't get a bad plug or something.

Drivibility: Off the line has literally zero get up and go. It falls hard, stumbles, and sometimes backfires. Then goes. Once in the RPMs the truck has power and launches hard to pass or whatever. Once the truck slips into OD, it surges pretty hard. So much in fact i keep OD off cause its annoying. There are times the computer see's that #7 misfire and refuses to run right at idle, sometimes stalling itself. Generally though, it'll hold its idle.

At this point I'm thinking a few things: bent valve, fouled plug, bad cap/rotor/wire, screwed up fuel sync. I have a friend, sort of, at a local dealership thats going to run a DRB to it. I'm not sure what that will tell about my truck, maybe everything. At this point I'm lost. Today is the first day i drove it to work in over a year and it was scary. Every other stop light was...ok I want to stall now....and required 2 footing. Mostly it'll regain itself, others requires a quick pedal hit to catch it.
The other point, whether makes a difference or not, is since the rebuild, the truck is difficult to turn over. I have a remaote system but can't use it. The truck won't start onits own without some pedal effort. And then its a slow start, not a insta one. Oh...and it reeks of fuel at the tail pipe. I mean pig rich. Funny thing here, on last dyno, I was 14+ leaning out at 5100+ top end. Odd I'd smell fuel when I know for a fact its lean...but I believe its the computer loading up.

I know this is a lot of information, but I wanted to be as detailed as i could for better answers. So...any thoughts guys?

Thanks!

mtlcafan79
03-12-2008, 12:46 PM
PHAT cam and poor drivability. Sounds over cammed to me. I'd talk to Hemifever for an SCT tune.

99BarneyRT
03-12-2008, 01:41 PM
PHAT cam and poor drivability. Sounds over cammed to me. I'd talk to Hemifever for an SCT tune.

Cam is the same one thats been in there for past 2 years. All I changed was the upper end portions. But, I do agree, I need a tune of some sort cause the 19lbs are not cutting it at all. I believe I need 28-30lbs in there, but B&G can't work with that and SCT, FAST, DKI Thruster does. I have a local shop here that does SCT, but he doesn't have the x2 kit so he can only do a basic can tune, which hs says will net me 90% of what i want. I doubt that, as the B&G is a can tune. But I don't think the tune is all my problem, but apart of it.

99BarneyRT
03-12-2008, 07:56 PM
Just an update, just returned from the dealership. I guess its somewhat good news, but not really. #7 missing like hell, truck barely running. Did a compressions check, zero. Um what? Did a leak check, intake valve stays open. SO, what this all means is either (A) broken spring or (B) bad valve. Least those are the smaller things. Looks like a possible head removal, uggg which sucks ass.

mtlcafan79
03-12-2008, 08:14 PM
I thought you changed cams at the same time. Heads are coming off. Hope it didn't make any custom pistons out of it. Yikes.

Talk to Hemifever and look into the SCT group buy. That'd be a much better deal than your local shop it sounds like.

99BarneyRT
03-12-2008, 08:20 PM
No sir, just more porting and different intake mainly. Same cam. But, its a little chill that crosses your back when you hear 'no compression" out of a technicians mouth. I'm like WTF! Once he hooked up the leak tester, air was flowing into the intake like made. He even turned the motor over a good 7-9 times, same.

I agree, I do need SCT/FAST/DFI something. The B&G isn't cutting it at all. The problem with the SCT that I'm worried with is a lot of bad publicity on the DD forums with fried PCMs and shit. Thats the last thing I want. I know some guy FAST, and now DFI thruster is out. Either way, 19lbs are too small and I need better tun-ability.

So, looks like I'm going back into the motor, ugg. Bad valve...stupidness. IF thats what it truly is. Never heard of springs going bad, not the .600 ones anyways.

mtlcafan79
03-13-2008, 02:43 AM
My 99 heads/cam 360 runs just fine on 24's with a Tom Fox flash. I wouldn't knock SCT just yet. The one guy that thought his PCM was fried was just a bad crank sensor. The other one or two people that I have seen were returned their tuners and working PCM's in the end. There's lots of other guys out there not on the forums or even on the forums that it works just fine for and you never hear from them.

Pull the heads. Hopefully yours looks better than this:

http://www.sincityrt.com/photos/drtc2004/DSC06543.JPG

meangreen
03-13-2008, 08:18 AM
No sir, just more porting and different intake mainly. Same cam. But, its a little chill that crosses your back when you hear 'no compression" out of a technicians mouth. I'm like WTF! Once he hooked up the leak tester, air was flowing into the intake like made. He even turned the motor over a good 7-9 times, same.

I agree, I do need SCT/FAST/DFI something. The B&G isn't cutting it at all. The problem with the SCT that I'm worried with is a lot of bad publicity on the DD forums with fried PCMs and shit. Thats the last thing I want. I know some guy FAST, and now DFI thruster is out. Either way, 19lbs are too small and I need better tun-ability.

So, looks like I'm going back into the motor, ugg. Bad valve...stupidness. IF thats what it truly is. Never heard of springs going bad, not the .600 ones anyways.


haha... I am one of the guys from DD with a fried PCM. And I did throw out some bad Pub, but only to stop people from throwing the SCT at their daily driver without knowing that there is good a possibility of their main mode of transportation going down. Just trying to help fellow dak owners.

After a few weeks I did get a brand new PCM and my tuner back. It's a great tool, and I like it alot. I would recommend it to someone who has another car, or an extra PCM.

99BarneyRT
03-13-2008, 08:59 AM
haha... I am one of the guys from DD with a fried PCM. And I did throw out some bad Pub, but only to stop people from throwing the SCT at their daily driver without knowing that there is good a possibility of their main mode of transportation going down. Just trying to help fellow dak owners.

After a few weeks I did get a brand new PCM and my tuner back. It's a great tool, and I like it alot. I would recommend it to someone who has another car, or an extra PCM.

Well this isn't my DD so thats no problem there. My only other PCM is factory PCM. The current one is B&G flash Mopar performance unit.


My 99 heads/cam 360 runs just fine on 24's with a Tom Fox flash. I wouldn't knock SCT just yet. The one guy that thought his PCM was fried was just a bad crank sensor. The other one or two people that I have seen were returned their tuners and working PCM's in the end. There's lots of other guys out there not on the forums or even on the forums that it works just fine for and you never hear from them.

Pull the heads. Hopefully yours looks better than this:


That would truly suck balls. I doubt it but who knows. I'll know little more when I get the intake off and valve covers off first. As for 24lbs...I was thinking that but was also thinking of maybe giving it a tad more. I'll look more into SCT...just want the issues that others have.