RyanInWheeling
Well-known member
the cars run fine until under load. as soon as it starts to boost it starts sputtering. found one vacuum leak by eye and fixed it but no help.its has spark. any ideas? thanks
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car is sputtering while building boost
- Thread starterRyanInWheeling
- Start date
Barnes
Well-known member
What is your spark plug condition and gap?
RyanInWheeling
Well-known member
new ngk plugs gapped at fac spec
RyanInWheeling
Well-known member
the car flooded out the otherday so i replaced the plugs. im starting to think that the o2 sensor might need replaced also
RyanInWheeling
Well-known member
going to regap at .028 when i get home and i guess since i have a mits o2 sensor i will install that as well
prove_it
Well-known member
How does it run at idle? If it's running poorly then you might have a coolant temp sensor that is reading wrong.
A little more detail helps us out more since we are not there. How does it idle, does it continue to sputter or does it clean out as you rise in RPM's, does it do it engine cold or hot or both? Does it blow black smoke out the tailpipe during the the sputter? Does it run and drive just fine under cruising?
Common issues that arise can include bad MAF sensors, boost leaks, vacuum leaks, broken/old wiring and hoses, bad temp sensors, bad O2 sensors.
A little more detail helps us out more since we are not there. How does it idle, does it continue to sputter or does it clean out as you rise in RPM's, does it do it engine cold or hot or both? Does it blow black smoke out the tailpipe during the the sputter? Does it run and drive just fine under cruising?
Common issues that arise can include bad MAF sensors, boost leaks, vacuum leaks, broken/old wiring and hoses, bad temp sensors, bad O2 sensors.
RyanInWheeling
Well-known member
It idles a little rough but that's normal Runs fine in all conditions until wot if you back off it gets better. But it ran fine until this flooding issue.
BoostedAWD91
Well-known member
Check your plugs now and see what they look like
prove_it
Well-known member
Sounds like the ECM is seeing a lean condition so it's dumping fuel in.
Do you have a logger or way to check your fuel trims?
Do you have a logger or way to check your fuel trims?
RyanInWheeling
Well-known member
Plugs look good not wet.... a little gray..q
SouthCaliVR4
Well-known member
First check your spark plug wires, then use a volt meter to check the 02, check more thoroughly for vacuum leaks. what caused the flood, short start (I.e. fired it up cold moved it a few feet & shut it off) or some other unknown condition?
RyanInWheeling
Well-known member
I short started it the night before then started it the next morning it started to stall I hit the gas as it did and it stalled.. happened again and then after just turned over wouldn't even fire.. I the Icleaned the plugs put them back and it fired. I drove it down road thinking it would clean out and has missed ever since
mitsuturbo
Well-known member
How are your ECU caps?
Do you have a logger?
Are you sure you dont have a boost leak?
How's compression?
Can you do a leakdown test?
Do you have a logger?
Are you sure you dont have a boost leak?
How's compression?
Can you do a leakdown test?
RyanInWheeling
Well-known member
I finally had the time to look into it and did a boost lea test. Turned out to be the intake manifold gasket.. thank you to everyone who replied. Much appreciated.. not to jump off subject but 955 now belongs to my girlfriend who should be joining board soon. I have since picked up 630/2000
