Constant Fuel Cut Off?

[nickmoss110]

Hi, I am new to this forum as I bought a Mazdaspeed Protg as my daily driver back in January of this year. When I bought the car it had a severe cylinder 3 misfire, I cured the misfire after replacing the plugs/plugwires/coils as well as all 4 fuel injectors. After having done that, I have been experiencing a bad jerking when the car is under boost. Upon further investigation, I found the stock charge pipe where the vacuum line from the air intake runs into the cold pipe was completely snapped so I just installed a corksport upper charge pipe (cold pipe) today. Problem still exists.. Can anybody help me get this car running the way it should, any information would be greatly appreciated guys! Thanks!!

 

[protege3690]

check for vacuum leaks. check all your lines, exhuast mani is nt cracked. and if your car jerks under boost before 4k rpms thats the ecu switching from open loop to closed loop i believe. these car have a bad tuning and stomping on the throttle at low rpms the ecu dumps a pig-rich mixture of fuel into the engine. use the search button and you can read all about it. plus haveing a stock IC setup (plastic intercooler and pipes) it heatsoaks quickly and definitely does not help with the crappy tuning the car already comes with. another thing, u mentioned u swapped out the plugs. MAKE SURE THEY ARE GAPPED CORRECTLY. between .028 - .033 , do not follow the manual for .044. thats for NA protege.

 

[nickmoss110]

I put iridium non gap plugs in it.

 

[protege3690]

I put iridium non gap plugs in it.

i would def still check the gapping on them. plugs may come pre-gapped but not always correctly for a specific model. just my 0.02 (2cents)

 

[Mysta316]

I put iridium non gap plugs in it.

What do you mean by this? Did the box say not to gap them? or are they the kind that don't have the part that comes over the tip of the plug? Do you have a boost gauge in the car? Ive been chasing down a fuel/boost cut in my car for a while now and I think I've got it figured out.I would check all of your vacuum lines for holes and make sure your intercooler piping is not cracked. Then check to make sure your wast gate is not leaking. Pull the hose off its source and with it still connected to the W/G make sure you cant blow and suck air into it. I just found that mine is totally shot.

 

[jeffmsp]

the obvious question-is the bypass valve installed in the correct direction? have you check the valve itself for leaks? they dont last forever and at 10 years old its something that could be causing issues like you described.

 

[thuzil]

Get copper plugs. Check Gap. Check for Vac leaks.
When stomping on the fuel with this car, you will quickly hit fuel cut because the stock map runs rich.
If you continue to have this issue after everything has been checked out, try a SSAFC

 

[nickmoss110]

What do you mean by this? Did the box say not to gap them? or are they the kind that don't have the part that comes over the tip of the plug? Do you have a boost gauge in the car? Ive been chasing down a fuel/boost cut in my car for a while now and I think I've got it figured out.I would check all of your vacuum lines for holes and make sure your intercooler piping is not cracked. Then check to make sure your wast gate is not leaking. Pull the hose off its source and with it still connected to the W/G make sure you cant blow and suck air into it. I just found that mine is totally shot.

The Box did say not to gap them. As I mentioned before, the cold pipe WAS cracked, so I replaced it with a corksport silicone one. I clean the MAF today (it was already spotless clean) I changed the air filter which was extremely dirty but nothing was really clogging it. Problem is still there. It's not so much fuel cut now that I left the battery unplugged overnight, now it is more of a cylinder misfire and the new check engine code is a Cylinder 3 misfire.. The system too lean code has gone away. Would the waste gate or any vacuum leaks cause the PCM to to specifically say a cylinder 3 misfire, or should I just try getting cheaper (copper) plugs?

 

[hornsfan10609]

The plugs you have will work fine if you gap them to .028-.032". I recommend NGK plugs, ZFR6F are the factory plug. When you buy plugs from the store they are gapped to .044" for an N/A protege. We have all been through this before, take our word for it and re-gap the plugs.

 

[nickmoss110]

The plugs you have will work fine if you gap them to .028-.032". I recommend NGK plugs, ZFR6F are the factory plug. When you buy plugs from the store they are gapped to .044" for an N/A protege. We have all been through this before, take our word for it and re-gap the plugs.

I have NGK's so I guess that's good, I'll take care of it A.S.A.P. and let you guys know how it worked out. Thanks.

 

[Maxx Mazda]

Do you have a boost gauge? What does it read? Sounds like you're overboosting and thus hitting fuel cut.

 

[nickmoss110]

I do not have a boost gauge in this car, I DO however, have a boost gauge in my Ion redline, I could probably hook it up real quick and see what it's boosting? I have a sorry excuse of a video I made to attempt to show you guys what exactly it was doing. But, like I said, it's a sorry excuse of a cell phone video in one hand and trying to drive with the other.. Also, off subject, how do I set my profile picture?

 

[nickmoss110]

Changed the gap on the plugs, running much better, but still has occasional fuel cut-off during boost, going to look at the Waste Gate Actuator and see if it fixes the problem, thanks for the ideas and the help guys.

 

[tweety2300]

If changing the gap in the plugs helped it could be spark blow out. A couple things to try are 1 step colder and gaped at .028, .032 or higher will cause issues, or in my case higher than .028