98.5 24 valve misfire?

Timmay · 05-05-2008, 06:05 PM

Towing my jeep (about 5.5k lbs with the trailer) to Rausch Creek this weekend I noticed the truck sucking a whole helluva lot more fuel than usual. I'm talking 8-9mpg. I also noticed 1100* or so EGTs on hills. FWIW, I tow on lvl 2 or 3 usually. Never have I had EGTs over 1000 towing to Rausch. I was on 2 to begin with, when I noticed the EGTs I dropped it to lvl 1. This helped some but I was still over 1000.

I also noticed on the way home, when I got stuck in traffic, the truck almost sounded like it was misfiring. If I lugged it into 3rd and 4th slighty it sounded like a jake brake. Cool and all, it's not normal.

Any idea whats wrong? There were no CELs. Boosts fine, 20-25 psi peak on the hills. Fuel pressure was maybe a little higher than usual, but I just put a new lift pump in.

I'm at a loss. Kinda thinking it's a clogged/toasted injector. I don't know how that would over fuel though.

Today I decided to try unplugging the Edge box to see if it was the problem. No change, but a CEL came on. I will run the codes when I get a chance.

Am I right to assume it's an injector issue? I don't mind upgrading, but I want to be sure it will cure my issues.

I need to move to Illinois in two weeks. I'd like to have this fixed before that.

__________________
Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

deez · 05-05-2008, 07:00 PM

sounds injectorish - crack one fuel line at a time to see which hole(s) is the prob. Then pull the inj. and see if you see anything wrong (missing tip). And if your oil level is over full you may have one dribbling. Just watch it closely, over fueling can do some bad bad things -

-good luck

__________________
96 1ton 4wd duely 12 valve 5 speed - turned the wheel, slid the plate custom 4'' exhaust, other than that its stock

Timmay · 05-06-2008, 07:22 AM

Thanks. I'll try and check that out soon. I don't have any tools up here at school so i'm kind of limited.

Someone braught up a good point about the APPS being out of adjustment. I'm also going to try and check that out.

__________________
Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

Last edited by Timmay : 05-06-2008 at 07:25 AM.

Smokinrebel · 05-06-2008, 07:29 AM

kind of almost sounds like lift pump might be going out...mine started cutting out aorund 2000rpms when my lift pump went out (before i had a fuel pressure gauge).

__________________
98 24V Edge Drag Comp, Injectors, 4in Straight Pipe, K&N Intake, Silencer Ring Removed, Pusher Pump, Georend Triple Disk Convertor and Valve Body w/ big shift kit All topped with a Loose Nut behind the wheel

Dad · 05-06-2008, 07:38 AM

Another good diagnostic for this type of issue is an infrared temp gun. You can get the temp of the exhaust at each port to see if one is cool.

High EGT's, low MPG's and 20 PSI of boost, assuming you have stock injectors, makes me wonder about the MAP sensor. Is the smoke level normal?

__________________
High Rider: 98.5 Ram 2500 4x4, 5 Spd, 4" TB Exhaust, BHAF, Gauges, FASS95, S-Chips Tune
Low Rider: '06 Chevy 1/2 Ton, Victory Red, 2/4 Drop, roll pan, sport mirrors, rollin on 20's

Timmay · 05-06-2008, 08:34 AM

Quote:

Originally Posted by Dad

Another good diagnostic for this type of issue is an infrared temp gun. You can get the temp of the exhaust at each port to see if one is cool.

High EGT's, low MPG's and 20 PSI of boost, assuming you have stock injectors, makes me wonder about the MAP sensor. Is the smoke level normal?

No, smoke is excessive. Would the MAP sensor cause an odd sound? Seems like maybe and overfueling issue would though.

It's very rythmic so i'm thinking it's concentrated in one cylinder, which is also why I thought it was an injector.

__________________
Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

Dad · 05-06-2008, 08:46 AM

Since you have a code, that would be a good first place to start. It may just be a MAP sensor and you're dumping way too much fuel in. That explains all the symptoms but the sound, which is hard to diagnose on a forum.

Here's some other ideas to rule some things out:

- If you have an infrared temp gun, you could get the temps on each exhaust port and see if you have a cold one.

- I would check to make sure you don't have a crankcase full of fuel.

- Pull the dipstick when it is running and see if you are getting a lot of blowby.

- Check the coolant and see if is contaminated with oil.

__________________
High Rider: 98.5 Ram 2500 4x4, 5 Spd, 4" TB Exhaust, BHAF, Gauges, FASS95, S-Chips Tune
Low Rider: '06 Chevy 1/2 Ton, Victory Red, 2/4 Drop, roll pan, sport mirrors, rollin on 20's

Timmay · 05-06-2008, 10:06 AM

Okay, with my limited amount of tools I just went out to check some stuff.

I was able to crack 5 out of 6 injectors. Every time the motor bogged some, so that means the injectors are fine there. I need to get a 19mm wrench to crack the #2 line. It's too close to the intake horn for my 3/4".

I also unplugged the edge from the MAP and plugged the stock harness in. No difference. I tried to run the codes with the key trick and it didn't work. I guess the older trucks it doesnt work.

How do I tell if there's fuel in the crankcase with the dipstick? Is it obvious? It looked like it always does when I checked it, just oily.

__________________
Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

clc · 05-06-2008, 12:20 PM

I'd love for someone to prove me wrong but it there is no key trick to read the codes on a 98.5.

With the dipstick. The crankcase fuller than the last time you changed/added oil is a good indication of fuel in the oil.

__________________
'96 3500 4WD dually club cab, 47RE, 3.55, gauges, #6 plate, 5", FASS, DSS, Line-X
'98.5 2500 2WD quad cab, SB, 5-spd, 3.55 Dana 80 LS, gauges, Superchips, 4", FASS, DSS, B&W turnover ball, Alcoa wheels, Line-X

Timmay · 05-06-2008, 12:37 PM

Yea I feel ya. I just ran over to autozone and had them run the codes. P0216 was the one that matters....

__________________
Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

05-05-2008, 06:05 PM	#1 (permalink)
Timmay Cummins Fan Join Date: Jun 2006 Posts: 62 Timmay's Truck Pics	98.5 24 valve misfire? Towing my jeep (about 5.5k lbs with the trailer) to Rausch Creek this weekend I noticed the truck sucking a whole helluva lot more fuel than usual. I'm talking 8-9mpg. I also noticed 1100* or so EGTs on hills. FWIW, I tow on lvl 2 or 3 usually. Never have I had EGTs over 1000 towing to Rausch. I was on 2 to begin with, when I noticed the EGTs I dropped it to lvl 1. This helped some but I was still over 1000. I also noticed on the way home, when I got stuck in traffic, the truck almost sounded like it was misfiring. If I lugged it into 3rd and 4th slighty it sounded like a jake brake. Cool and all, it's not normal. Any idea whats wrong? There were no CELs. Boosts fine, 20-25 psi peak on the hills. Fuel pressure was maybe a little higher than usual, but I just put a new lift pump in. I'm at a loss. Kinda thinking it's a clogged/toasted injector. I don't know how that would over fuel though. Today I decided to try unplugging the Edge box to see if it was the problem. No change, but a CEL came on. I will run the codes when I get a chance. Am I right to assume it's an injector issue? I don't mind upgrading, but I want to be sure it will cure my issues. I need to move to Illinois in two weeks. I'd like to have this fixed before that. __________________ Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

05-05-2008, 07:00 PM	#2 (permalink)
deez Newbie Join Date: May 2008 Location: va Posts: 2 deez's Truck Pics	bad bad things sounds injectorish - crack one fuel line at a time to see which hole(s) is the prob. Then pull the inj. and see if you see anything wrong (missing tip). And if your oil level is over full you may have one dribbling. Just watch it closely, over fueling can do some bad bad things - -good luck __________________ 96 1ton 4wd duely 12 valve 5 speed - turned the wheel, slid the plate custom 4'' exhaust, other than that its stock

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05-06-2008, 07:22 AM	#3 (permalink)
Timmay Cummins Fan Join Date: Jun 2006 Posts: 62 Timmay's Truck Pics	Thanks. I'll try and check that out soon. I don't have any tools up here at school so i'm kind of limited. Someone braught up a good point about the APPS being out of adjustment. I'm also going to try and check that out. __________________ Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc. Last edited by Timmay : 05-06-2008 at 07:25 AM.

05-06-2008, 07:29 AM	#4 (permalink)
Smokinrebel Diesel Freak Join Date: Jul 2007 Location: Cincinnati Posts: 506 Smokinrebel's Truck Pics	kind of almost sounds like lift pump might be going out...mine started cutting out aorund 2000rpms when my lift pump went out (before i had a fuel pressure gauge). __________________ 98 24V Edge Drag Comp, Injectors, 4in Straight Pipe, K&N Intake, Silencer Ring Removed, Pusher Pump, Georend Triple Disk Convertor and Valve Body w/ big shift kit All topped with a Loose Nut behind the wheel

05-06-2008, 07:38 AM	#5 (permalink)
Dad Administrator Join Date: May 2007 Location: Indiana Posts: 3,196 Dad's Truck Pics	Another good diagnostic for this type of issue is an infrared temp gun. You can get the temp of the exhaust at each port to see if one is cool. High EGT's, low MPG's and 20 PSI of boost, assuming you have stock injectors, makes me wonder about the MAP sensor. Is the smoke level normal? __________________ High Rider: 98.5 Ram 2500 4x4, 5 Spd, 4" TB Exhaust, BHAF, Gauges, FASS95, S-Chips Tune Low Rider: '06 Chevy 1/2 Ton, Victory Red, 2/4 Drop, roll pan, sport mirrors, rollin on 20's

05-06-2008, 08:46 AM	#7 (permalink)
Dad Administrator Join Date: May 2007 Location: Indiana Posts: 3,196 Dad's Truck Pics	Since you have a code, that would be a good first place to start. It may just be a MAP sensor and you're dumping way too much fuel in. That explains all the symptoms but the sound, which is hard to diagnose on a forum. Here's some other ideas to rule some things out: - If you have an infrared temp gun, you could get the temps on each exhaust port and see if you have a cold one. - I would check to make sure you don't have a crankcase full of fuel. - Pull the dipstick when it is running and see if you are getting a lot of blowby. - Check the coolant and see if is contaminated with oil. __________________ High Rider: 98.5 Ram 2500 4x4, 5 Spd, 4" TB Exhaust, BHAF, Gauges, FASS95, S-Chips Tune Low Rider: '06 Chevy 1/2 Ton, Victory Red, 2/4 Drop, roll pan, sport mirrors, rollin on 20's

05-06-2008, 10:06 AM	#8 (permalink)
Timmay Cummins Fan Join Date: Jun 2006 Posts: 62 Timmay's Truck Pics	Okay, with my limited amount of tools I just went out to check some stuff. I was able to crack 5 out of 6 injectors. Every time the motor bogged some, so that means the injectors are fine there. I need to get a 19mm wrench to crack the #2 line. It's too close to the intake horn for my 3/4". I also unplugged the edge from the MAP and plugged the stock harness in. No difference. I tried to run the codes with the key trick and it didn't work. I guess the older trucks it doesnt work. How do I tell if there's fuel in the crankcase with the dipstick? Is it obvious? It looked like it always does when I checked it, just oily. __________________ Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.

05-06-2008, 12:20 PM	#9 (permalink)
clc Cummins Fan Join Date: Feb 2008 Posts: 46 clc's Truck Pics	I'd love for someone to prove me wrong but it there is no key trick to read the codes on a 98.5. With the dipstick. The crankcase fuller than the last time you changed/added oil is a good indication of fuel in the oil. __________________ '96 3500 4WD dually club cab, 47RE, 3.55, gauges, #6 plate, 5", FASS, DSS, Line-X '98.5 2500 2WD quad cab, SB, 5-spd, 3.55 Dana 80 LS, gauges, Superchips, 4", FASS, DSS, B&W turnover ball, Alcoa wheels, Line-X

05-06-2008, 12:37 PM	#10 (permalink)
Timmay Cummins Fan Join Date: Jun 2006 Posts: 62 Timmay's Truck Pics	Yea I feel ya. I just ran over to autozone and had them run the codes. P0216 was the one that matters.... __________________ Tow rig/DD: '98.5 2500 24valve, NV4500 swapped behind a 13" SBC Con "O", 4.10s, 315/70R17 MTZs on 3rd gen alloys, Edge Juice w/Attitude, BHAF, 4" MBRP etc etc.