engine misfires under full throttle

smyrnaman · 11-27-2005, 06:22 PM

My 2001 Ram Air runs great except under full throttle, It surges and misses very badly under full throttle. I checked for codes and it does not set any codes and the check engine light is not on. Anyone have any ideas the car has about 80000 miles on it

**WS6ICK** · 11-27-2005, 06:26 PM

What is your RPM's when it starts missing?

smyrnaman · 11-27-2005, 06:33 PM

It would appear that it is just a case of heavy throttle or full throttle, I can cruise at 2500 in high gear and it runs great but if I put my foot in it it misses and surges badly

**NeeD4SpeeD** · 11-27-2005, 06:45 PM

AHHHH sounds familiar...... I had the same problem man.. Check ALL the ignition wires i'll bet one is alittle loose!!! That was the SAME problem for me and the ignition wire for cylinder 4 was slightly loose and was jumping a spark just enough to make connection but not enough to throw a code.. Give it a shot!!!

smyrnaman · 11-27-2005, 06:47 PM

Thanks I will check, if anyone else has had a similar problem please come on in. I did change the plugs about 3000 miles ago.

redls1bird · 11-27-2005, 06:54 PM

what do you mean by surging? is it an auto or manual? technically it cant "surge" because of the way the drivetrain is connected. the only real way to effect the rpms is the throttle..

smyrnaman · 11-27-2005, 06:57 PM

It acts like it is starved for fuel and then regains it self for a moment then it starts all over again. Similar to turning your key off and on quickly.

02 Blk T/A WS6 · 11-27-2005, 07:11 PM

1 of your plugs is loose causing it to arch when you lay into it. happen to me once check your plugs

**NeeD4SpeeD** · 11-27-2005, 07:20 PM

Originally Posted by 02 Blk T/A WS6

1 of your plugs is loose causing it to arch when you lay into it. happen to me once check your plugs

Exactly what i said i just fixed that EXACT same symptom problem a month ago... CHECK THE WIRES!!!!Make sure there in real tight like virgin!!!

02 Blk T/A WS6 · 11-27-2005, 07:26 PM

Originally Posted by NeeD4SpeeD

Exactly what i said i just fixed that EXACT same symptom problem a month ago... CHECK THE WIRES!!!!Make sure there in real tight like virgin!!!

haha ya i remember that thread i posted on there suggesting you check your plug wires

**NeeD4SpeeD** · 11-27-2005, 07:29 PM

Originally Posted by 02 Blk T/A WS6

haha ya i remember that thread i posted on there suggesting you check your plug wires

Yup and it worked man!!!

99PontTA · 11-27-2005, 07:40 PM

Originally Posted by smyrnaman

My 2001 Ram Air runs great except under full throttle, It surges and misses very badly under full throttle. I checked for codes and it does not set any codes and the check engine light is not on. Anyone have any ideas the car has about 80000 miles on it

have you changed the fuel filter lately?That would be a good place to start......then if that doesn't help check the fuel pressure.Surging at moderate to heavy throttle is a sure sign of a fuel problem...Spark plug wire trouble usually causes a miss or bucking...not surging.

smyrnaman · 11-27-2005, 07:53 PM

Thanks for all the input everyone, I will tackle this first thing on Monday.

**NeeD4SpeeD** · 11-27-2005, 07:58 PM

Originally Posted by smyrnaman

Thanks for all the input everyone, I will tackle this first thing on Monday.

N/p let us know how it goes!!!! And good luck!!

smyrnaman · 11-28-2005, 06:35 PM

Tried it all and it still is missing at full throttle, the car runs great at all other throttle conditions. How would the O2 sensor affect full throttle?

99PontTA · 11-28-2005, 07:26 PM

they won't.......next thing i would do is no 1.check fuel rail and lines for rust contamination, no 2 check fuel pressure.read this http://service.gm.com/gmtechlink/ima...me.html#story7
its possible the screens are partially blocked in the injectors.CHECK THE fuel pressure with a gauge..its important to know what you are working with.My 99's fuel rail was so badly rusted it blocked most of the screens with rust...car ran terrible.Before it got it really bad the car would SURGE as you accelerated and MISS at WOT....then i put some fuel system cleaner in it....that finished it completely because it lossened all the rust and totally blocks ALL the injectors.