MSP 03.5 Sputtering

Hey folks, just recently in the dead of winter my MSP has a pretty bad issue with sputtering, it sputters lightly while idle, and when the RPM is between 1k-3.5k it sputters heavily, it jerks a bit. My wideband reads 14.5 - 17.5 idle, is that very lean right? Good or bad? and its smells like heavy fuel while idling for more than 5 minutes in the cabin.
I always run .93 octane and usually take advantage of the octane boost by STP...its amazing when doing pulls, recently I just stop using it (budget issue)
I am using Unichip PnP, should I be using MAP A or B?
My vac line is good with the standard of 20 on the boost gauge during idle
Could it be my spark plugs?
MAF?
ECU?

I have a couple CEL that just recently popped up as well, I believe one is
P0660
and I'll get the other code in the morning...
 
that code is for your manifold butterfly valves. That might be the cause of your issues.
Get all the codes to point you in the right direction before making too many assumptions.


17.5 is very lean. Stoichiometry is 14.7:1 for gasoline. your air fuel ratio at no(idle) or very little load(cruising) should hover around the figure cycling from slightly rich to slightly lean.

Check your spark plugs, specially if you are running lower heat range plugs in this weather.
 
*I have a Mazda 626 intake manifold, for the butterfly delete...
*I guess my first step is to replace my plugs, I saw a lot of information on plugs somewhere in the MSP forum, but any
recommendations?
*I still run off wastegate ~7 PSI.
*Should I get 1 step colder plugs, or anything for this Northern Virginia really cold weather ?
 
Stay with stock heat range(6) plugs.

Other things to check would be the wires and the coils. Make sure you're getting a good spark. But when you take out the plugs you should be able to see if there are any combustion issues by the condition they are in.
 
hmmm, intereseting, but yea the codes I have are the ones I always have P0660 and P0421, just cauz the intake manifold and cat delete, nothing out the ordinary.
but...
I will change my plugs and examine them, I am a noob so I don't know what to look for. I will check my wires and coils as well.
Thanks for the advice ap123 not sure if Ive seen you around the area with the P5
 
Okay so I changed my spark plugs to the new NGK ZFR6 replacing the old NGK ZFR7, it fixed the problem ! But now, I can't boost for some reason when I want to apply more gas it doesn't go any faster or step into boost on my gauge, is that considered fuel cut ? I might need the 1 step colder plugs NGK ZFR7 ?
 
Sorry my plugs that I pulled were ZFR7F-11 not ZFR7F big difference in gap size !
Anyways they were gapped at .30, .39, .39, and .35 its suppose to be a .44 like my new ZFR6F-11
What does a shorter gap mean ?
 
You need to pull the ZFR6F plugs you have now and close the gap down to .028-.030", then the car will run correctly. .044" gap is for regular Proteges. ZFR6F plugs are the correct small gap, ZFR6F-11 are what the parts stores sell and must be adjusted for the MSP.
 
Wow thanks for that information hornsfan10609 ! Ill pull them I think tomorrow ! But why does the MSP use a smaller gap, what does that mean ? Still in the learning process !

You guys should def. check out my mods on my page and put in some thought/recommendation
 
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Any check engine light? When you turn the key to the on position do you hear the fuel pump turn on? Will it turn over?
 
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