2G Backfire/Miss/Hesitation

[XiKeiyaZI]

Alright. So going to make this as short and as detailed as possible. Upon deceleration, the vehicle is suffering from miss/backfire. Also, when I am accelerating, the boost will pick up but the car will not begin to pull until about 2,500RPMs.

::Symptoms::
Backfire from Decel
Hesitation to accelerate
Slightly bad gas mileage
Unplugging 02 Sensor does nothing to the performance of the car
CEL which is reading 2 codes. One for Purge Control Solenoid. One for EGR Solenoid.

::Fix Attempts::
Reset ECU. Will 'click' every so often until CEL comes on.
Installed Thermostat. PO removed this.
Pulled Fuel Rail and soaked injectors in cleaning solution.
Checked for leaks. System is tight.
Changed Spark plugs. BPR7ES at .028. Tried BPR6ES' as well.


I recently also noticed that the spark plug wire for Cylinder two was slightly melted. I traced this back, and it looks like the coil closest to the Timing Belt has heat damage? =/

Any input would be appreciated. As much detail as you can give would be great.

Thanks.

 

[dsmdeliveryboy]

Do a compression test, see if you have a dead cylinder.

 

[XiKeiyaZI]

Compression is 160 Across the board.

Dry Test.

 

[XiKeiyaZI]

I was just thinking... dropping a cylinder, the car would run like complete ass... What the hell was I thinking doing another comp test that late?

Anyway.

:I had a bad wire at the battery ground. Got that resolved in the mean time. I might have a leak in the hose running from my IM to my FPR...going to take a look at that and see.
:Checked timing.. it's correct.
:Checked Throttle position. It's correct.
:Checked wiring to injectors. All are snug and look good.

What, the HELL could be wrong?

 

[motozachl]

So only under 2.5k it runs like garbage? How's the idle? Did you replace the plug wire?

 

[GSXSixteenG]

I was going to try holding off replying on one of your threads for once, but I was thinking along the same lines as motozach. Get out your volt meter and test your coil packs and plug wires.

Also, have you check the plug valley gaskets or maybe cracked valve cover, any moisture or oil in there can cause missing or hesitation.

 

[ramsack]

Backfire from Decel

It should not do this. This would tell me your TPS is not showing closed or you have a leaky injector. Soaking them in a solution doesn't clean them, or fix them if they are damaged. They need to be cleaned ultrasonically, and this still doesn't guarantee anything.

Reset ECU. Will 'click' every so often until CEL comes on.

Are you 100% sure your ECU is good. That clicking is the MPI relay. One of the symptoms of a failing ECU because of capacitor problems is that relay clicking. The relay could also be bad and you could be not getting good voltage to the fuel pump, unless you have that rewired.

Testing a burnt coil pack will tell you nothing. It can be damaged on the outside and let moisture in, and make your car run like crap, and still show on a multimeter as good. I would replace it just because of that being burnt. This can also trigger a CEL if you have a short from moisture and cause that clicking. Oil is mostly dielectric and won't cause any trouble if a little bit is down in the plug wells, but it still tells you to replace those gaskets if there is oil down there, because oil will deteriorate your plug wires. I would go and get a set of NGK wires, part number 8100 (sometimes ME77). They are as close to stock as you will get without paying through the roof at a dealer.

 

[XiKeiyaZI]

I won't even quote all of the above since I know you guys pretty well. ;P
I'll just go through the paces here.

1 : Found out that the Clicking was a bad post on the battery. I JUST replaced it when I left for lunch. No more clicking. I pulled the ECU. Looks perfect.
2 : There is no oil in the spark-plug cylinders. =/ I hate leaky valve covers.
3 : I didn't even think about the TPS.
4 : The Coil.. I've been looking for my spare one to replace it. Just haven't found it yet. It's not Melted into, per say, just more of the wiring harness cover that bolts onto the IM(that has the plugs for the injectors) got hot for some unknown reason when the PO had it and melted onto the coil pack. It discolored it a bit... but I suppose it's better safe than sorry and I need to replace that ASAP.
5 : Still there's the issue with the 02 Sensor. If I unplug it, the car shows no changes.
6 : I soaked the injectors and worked the pin at the bottom. Applied some air and could hear it snap closed and cut off air flow. I did the same thing with my 1G and one of the injectors that WAS dirty cleared up and worked perfect afterward. Now, I have 2 Bluetops left from the 1G... would those work as replacements?

The reason I'm questioning these things is because it doesn't make sense that it's backfiring on Decel, well, not until now that Ramsack pointed out the TPS. The Injectors are simply not supposed to deliver fuel on Decel over 2K, correct?

+1 for you guys, btw.

 

[ramsack]

I would check to see if your O2 is cycling at idle. If it isn't then you either have an exhaust leak or the sensor/wiring is bad. The TPS could just be misadjusted still with the whole idle switch inside thing. And it should fuel cut with closed throttle above 1500 rpm, not 2k.

 

[GSXSixteenG]

Magnecor Race Wires: Mitsubishi twin cam technical bulletin

Heres the link posted on vfaq I was referring to. I guess they have it all wrong.

 

[ramsack]

Oil is different than water. Pour water down that hole and see if it will run. Try oil then, it will run fine. As I said oil will ruin the wires over time, but it will not make arcs to the side of the well like water will. Any decent wire also will not let any kind of moisture up into where the wire connects to the plug. Dielectric grease is a good idea, leaks or not, to help seal and keep moisture out of there.

 

[XiKeiyaZI]

-reading above link- God, if only the rest of the people who post would read the shit they are linked. You know how much I've learned from random links? Hahah.

The Plug wires are NGK's, the pretty blue ones. It's sad to sit here and think that they are ruined. =/

So I suppose my best choice would be to test/replace the coils, drop $75-$150ish on new plugs, 02 Sensor, and mess with the TPS? DSMLink keeps looking further and further away....

I also have a few connectors that I need to Take pictures of and post here... and find a way to get rid of my CEL for the EGR and Purge control Valve Solenoids..

 

[ramsack]

DSMLink would be the only thing to get rid of those CELs without plugging them back in.

 

[XiKeiyaZI]

DSMLink would be the only thing to get rid of those CELs without plugging them back in.

Don't happen to have any spare one laying around, do you? PO thought it'd be a good idea to pull em' toss em' and leave half of the emissions hanging under the car.

 

[ramsack]

Nope. I have no extra parts anymore.

 

[Jonman409]

Hey, I have most of my emissions laying around if you were trying to just get rid of the cel until dsmlink. I may also have a spare coil pack and other misc stuff I could ship out to get this figured out.

 

[XiKeiyaZI]

Hey, I have most of my emissions laying around if you were trying to just get rid of the cel until dsmlink. I may also have a spare coil pack and other misc stuff I could ship out to get this figured out.

I don't need the emissions stuff, per say.. but the PO just tossed the EGR and Purge Control Solenoids when they TRIED to do an Emis-Delete. >.< So I'm getting a CEL because those aren't there.

Shoot me a PM about that Coil... I can't find mine anywhere.

 

[Jonman409]

Sure, i'll try to check tonight when I get home. I'm 95% sure I have the solenoids too.

 

[XiKeiyaZI]

So will Bluetops work on this 2g? >> Cause I found 4...

 

[boosteclipse]

Hey man, I have for 2g 450 injectors you are welcome to swap and see if it helps, probly have the solenoids laying around. Need to get together.

 

[ramsack]

No, they have different fueling. Part of why my 1g runs kind of bad (2g black 450's)

 

[XiKeiyaZI]

No, they have different fueling. Part of why my 1g runs kind of bad (2g black 450's)

That's what I was curious of.. =/ Didn't know what the difference in the two were...But Booste up there lives about an hour from me. I might drive out to his place this weekend and see what we can come up with.

 

[Jonman409]

Sorry man, couldn't find the coil just the solenoids and 2 spare injectors.

 

[XiKeiyaZI]

Sorry man, couldn't find the coil just the solenoids and 2 spare injectors.

It's cool man. I can come across a Coil somewhere.

PM me in regards to what you want for that stuff. Gotta get rid of this miss and CEL. >.<

 

[92_6bolt_1290]

I'm having almost the same issue...and it tends to happen around 2000to 2500 rpms when i go from low throttle to high throttle very quickly. it doesn't matter exactly how much i put my foot down, it stutters for a couple seconds then gets up and moves. it will also do it at higher rpms as well when i suddenly push the throttle down more, CEL came on when it started happening too and i really am thinking TPS but i would rather not buy one unless i know thats what my problem is. my car also seems to be running richer than before too even though i didn't change my tune on it with my safc2. i know is running richer than before because its spitting out black smoke and will shoot out some flames up top.