[RESOLVED] misfire help P0300 - ISC & coil results

[bboyalan]

Hey guys! I've been trying to fix this w/ my dad since Friday night, but I must resort to asking for help now as it is simply too time consuming w/ college and all...

Long story somewhat shorter [so I can explain the current situation]:
-A'PEXi dp + high flow cat installed friday noontime [nice, powerful drive home]
-installed boost/vac gauge on that friday afternoon [easy source taps]
-tried drilling through passenger footwell w/o looking
-ended up going through steering wheel boot [success!]
-key in ignition = no go for instrument cluster
-car would crank, but not start
-ends up I drilled through the wires behind and beneath the battery...
-reconnected and wrapped up wires
-car cranks, starts, but has terribly low, bogging idle [200RPM near death]
-smells like unburnt gas [not enough air in mixture for combustion?]
-checked plugs and wires
-replaced 1-month old NGK G-power platinums [toasted] w/ *new* NGK iridiums
-did the throttle SAS + BISS adjustment properly to help idle @ 400-500 RPM
-test drove and had POOR acceleration + threw p0300 code for random misfire
-erased code & grounded the brown plug for ignition timing adjustment
-boost and vac leak check
-test drove again w/ the same poor acceleration, P0300 code, but <400RPM now

SO NOW [and I apologize for the brief summary] I'm here w/ some diagnostics/results and hoping to get some good direction and recommendations. We pulled the plugs out after the code was thrown to see if any weren't firing and they all checked out okay. I also tested the ISC [Idle Speed Control] and came up with 41 Ohms on each [supposed to be 28-33]. In addition, I tested both the primary and secondaries of my coil pack. The secondary checks out within proper range, BUT the primaries were showing 11.2 for each [should be 0.70 - 0.86]. My NGK wires are 1-month old and have good resistance in them.

What should I be testing for or replacing next? I have such a terrible headache from thinking about this on the constant and I've devoted practically ALL of my study time towards searching the forum + trying out new things. If there is any other information that's needed, then I'll try my best to provide them. Any help is appreciated!

ps: this thread seems to have a similar problem minus the first half of b.s. I had went through.

 

[Artago]

tom, i assure you that you would know if that little bastard fuel pressure solenoid was going bad. that was the first thing i had to do to my gst when i bought it 6 years ago. the car died at every stop sign and would accelerate for crap. felt like extreme ignition retard.

anyways, i have really bad news. the alternator did nothing, and i mean nothing at all. the car still does the exact same thing, idles at only 100 rpm's. this is really getting old. i'm suppose to be starting a new job, its Goodyear Tire, within a couple of weeks and i need this car goin. oh well, i've got an old truck that i can drive i guess until i get my gst going or buy something else for a work car.

i suppose my next option is the ecu swap. you still wanting to do something on that tom?? or are you keeping the one you have or what?? just pm me and we'll work something out if you want, if not i'm sure i can always find a late model thats still good that someone's throwing away for an eprom.

Here's the Plan: I plan to contact Auto Parts Fast at RockAuto and see if they carry EPROM ecu's. I checked their site but I don't know if the ECU's they carry are EPROM or not. If they are EPROM then I'll send my old ECU in for the core charge and get a new one (reman). Then once I get the reman unit I'll send it off to get it DSMlinked. When it comes back then I'll install it and the 97 non-EPROM ECU is all yours. Sound ok?

PS: The EPROM ECU is on LOAN from another local DSM but I'm 99.99% sure he wants to sell it.

 

[super97gst]

Here's the Plan: I plan to contact Auto Parts Fast at RockAuto and see if they carry EPROM ecu's. I checked their site but I don't know if the ECU's they carry are EPROM or not. If they are EPROM then I'll send my old ECU in for the core charge and get a new one (reman). Then once I get the reman unit I'll send it off to get it DSMlinked. When it comes back then I'll install it and the 97 non-EPROM ECU is all yours. Sound ok?

PS: The EPROM ECU is on LOAN from another local DSM but I'm 99.99% sure he wants to sell it.

yea, thats fine. if you talk to him and he does want to sell the eprom ecu let me know. i wasnt really planning on running dsmlink, but if i can come up with an eprom ecu then i guess i will. thanks

 

[Artago]

yea, thats fine. if you talk to him and he does want to sell the eprom ecu let me know. i wasnt really planning on running dsmlink, but if i can come up with an eprom ecu then i guess i will. thanks

Wait a second... You know someone selling and EPROM ECU? Can I buy it instead? (And I'll sell you mine) I need a EPROM.

Thanks.

Tom

 

[super97gst]

Here's the Plan: I plan to contact Auto Parts Fast at RockAuto and see if they carry EPROM ecu's. I checked their site but I don't know if the ECU's they carry are EPROM or not. If they are EPROM then I'll send my old ECU in for the core charge and get a new one (reman). Then once I get the reman unit I'll send it off to get it DSMlinked. When it comes back then I'll install it and the 97 non-EPROM ECU is all yours. Sound ok?

PS: The EPROM ECU is on LOAN from another local DSM but I'm 99.99% sure he wants to sell it.

oh sorry, i thought you were saying right here the one you had borrowed was an eprom. just got a little confused. sorry

 

[Artago]

oh sorry, i thought you were saying right here the one you had borrowed was an eprom. just got a little confused. sorry

No no no. The one I borrowed is non-EPROM. My original ECU is EPROM but I'm sending that in for a core charge. If you know someone who has a EPROM ECU for sale then please let me know. Would help me out.

Thanks,

Tom

 

[bboyalan]

Just a mini-update here:

So I was at my girlfriend's house this afternoon for her little sister's birthday when I had last posted on here. I was thinking of a quick test to see if the biss screw was leaking, SOOO I took her santa clause eraser, chopped its head off, and screwed in/plugged my biss screw's hole. The drive home didn't change much though, but there's more! In the garage, I was adding additional hose clamps and zipties to all remaining vacuum lines that weren't already "extra-secured". As I was doing the one on my BOV, I noticed that the vacuum nipple on it wasn't screwed in all the way [wtf?!]. It has never leaked noticeably before, so I have NO IDEA how it could undo itself or if it would make a difference - maybe it was all the engine bogging @ idle moments? Anyway, I tightened that as well. I didn't get a chance to test drive tonight, so I'll post back results tomorrow!

 

[Artago]

Update:

So still no P0300 code... but the P1105 code is back and a P0302 (Cylinder 2 misfire) has shown up. Sigh. This is getting annoying.

Tom

 

[super97gst]

well, its pretty obvious that the ecu swap did fix the major problem on yours and bboyalan's. but there obviously must be something else we're missing here. what else is there that effects each individual cylinder, that can cause these random misfires we're having?? is it possible the ecu, or at least a portion of it, could have gone out and affected some other sensitive area of the engine?? possible 02 sensor maybe. but i would think if the 02 sensor was malfunctioning the new ecu would throw a code for it.

i agree with you tom, this is really getting old.

 

[Artago]

well, its pretty obvious that the ecu swap did fix the major problem on yours and bboyalan's. but there obviously must be something else we're missing here. what else is there that effects each individual cylinder, that can cause these random misfires we're having?? is it possible the ecu, or at least a portion of it, could have gone out and affected some other sensitive area of the engine?? possible 02 sensor maybe. but i would think if the 02 sensor was malfunctioning the new ecu would throw a code for it.

i agree with you tom, this is really getting old.

I don't know but I have a new O2 sensor, it cycles nicely so I doubt it's bad. The only new code is the P1105 (FP solenoid code) so that might be worth checking out.

At least I'm throwing a P0302 now instead of P0300. So I'll try swapping the ignition coils and see if the problem moves from cylinder 2 to another cylinder. I'll also try a new FP Solenoid but I'm not sure if that will make a difference.

Tom

 

[voodoogsx]

well, its pretty obvious that the ecu swap did fix the major problem on yours and bboyalan's. but there obviously must be something else we're missing here. what else is there that effects each individual cylinder, that can cause these random misfires we're having?? is it possible the ecu, or at least a portion of it, could have gone out and affected some other sensitive area of the engine?? possible 02 sensor maybe. but i would think if the 02 sensor was malfunctioning the new ecu would throw a code for it.

i agree with you tom, this is really getting old.

I've heard that the capacitors can leak and cause various issues but this is usually on 1g's. Though, when I sent my ecu to get chipped, mine had apparently started to leak. The guys over at ecmtuning(dsmlink) took care of it, cleaned it up, and put new, better caps in it. Just a thought.

Glad to see some of the other issues were resolved though! Good work on that!

 

[bboyalan]

Tom: I'm sorry to hear about that =/ but hang in there! We're ALL going to get through this!

I'm on the same thinking path as super97gst that POSSIBLY our initial problems have affected or caused others. I try to not think about it that way despite how true it might be.

Mini-update on my part [no CELs so far...]:
So tightening the vacuum nipple on my bov didn't do much of anything for my drive to/from school+work and home. I DID notice something crazy when I came home though! One of my vacuum hoses blew off.... I've attached a picture to show which one it was. I double ziptied it, tightened the TB bolts, and drove to my 2nd part-time job - holds a little better but the leak is still noticeable. It sounds like its coming from the manifold area and I'd hate to think it's the damn gasket. Anyway, I double ziptied EVERYTHING I could get my hands on and will report back on that tomorrow afternoon.

Good luck everyone!

PS: 1k-1.2k idle surge + boost leak = TERRIBLE MPG..... I had a full tank of gas on Friday evening and drive mostly freeway despite the crap acceleration. I end tonight w/ ~160 miles and nearing 1/4 tank...... I seriously need to find the time + compressor for a true BLT.

 

[Artago]

PS: 1k-1.2k idle surge + boost leak = TERRIBLE MPG..... ...... I seriously need to find the time + compressor for a true BLT.

Took the words right out of my mouth.

Tom

 

[super97gst]

that was the very first thing i did when all this started was do a boost leak test. i filler her up to 20psi and it leaked off 1psi about every 2 seconds. i think that's pretty good isn't it?? and i could only find one leak, it was at the bov. actually it was leaking a little bit from the adjustment screw on the top of my greddy rs, just barely though. thats the first time i've done a boost leak test, maybe i didnt do it right though

 

[Artago]

So the beast is back. Let me give you all a time line:

Day 1:

P1105 (Fuel Pressure Solenoid)
P0136 (Rear O2)
P0302 (Cylinder 2 misfire)

Day 1.5:

P1105 (Fuel Pressure Solenoid)
P0136 (Rear O2)
P0300 (RANDOM Cylinder misfire)

Day 2:

P1105 (Fuel Pressure Solenoid)
P0136 (Rear O2)
P0302 (Cylinder 2 misfire)

At no point did I clear the codes. Notice how the P0302 code changed to a P0300 and then changed back to a P0302. Strange huh?

So which cylinder is #2?

I swapped my 95 ECU for a 97 ECU and had to swap the plug wires, so is Cylinder 2 being misreported as Cylinder 3?

What should I do to diagnose the misfire?

Also, the P1105 is the fuel pressure solenoid, where can I get one besides a dealer? (They want $140 for it WTF)


Thanks,

Tom

 

[super97gst]

So the beast is back. Let me give you all a time line:

Day 1:

P1105 (Fuel Pressure Solenoid)
P0136 (Rear O2)
P0302 (Cylinder 2 misfire)

Day 1.5:

P1105 (Fuel Pressure Solenoid)
P0136 (Rear O2)
P0300 (RANDOM Cylinder misfire)

Day 2:

P1105 (Fuel Pressure Solenoid)
P0136 (Rear O2)
P0302 (Cylinder 2 misfire)

At no point did I clear the codes. Notice how the P0302 code changed to a P0300 and then changed back to a P0302. Strange huh?

So which cylinder is #2?

I swapped my 95 ECU for a 97 ECU and had to swap the plug wires, so is Cylinder 2 being misreported as Cylinder 3?

What should I do to diagnose the misfire?

Also, the P1105 is the fuel pressure solenoid, where can I get one besides a dealer? (They want $140 for it WTF)


Thanks,

Tom

i couldn't find anywhere else to get one. i had to pay the 140. about the ECU, thats what's gonna throw the codes, so since you've swapped ecu's and you changed the plug wires the ecu is throwing the exact right code. what i'm saying is it shouldn't matter which ecu you have, if it's a #2 misfire it will throw that one, if its random it'll be a po300. i think it just cant figure out exactly which cylinder is misfiring so it just says random. that's all in the ecu.

i see you have a rear 02 code. i also have that one. mine is because i eliminated the cat with my downpipe. i just havent done a rear 02 eliminator yet. could this be causing some of our problem?? i noticed a lot of the wires that go into the rear 02 on mine have been broken or have come loose.

 

[bboyalan]

Tom: That's pretty weird to have the rear o2 code being thrown up each time. I saw that you had an OBX high flow cat installed. I also have a 3" high flow cat, but no code on my part. Perhaps something's going crapola with your air/fuel mixture? Also, the only idea I have for checking your random misfire is to pull the plugs and see which one isn't burning properly. As I had previously reported, 1 & 2 had the buildup whereas 4 & 3 were good looking.

mini-update again:

I was searching up on my GReddy RS bov [authentic] and found that many people have ran into a leaking one. I managed to wrap teflon tape around the adjustment screw and the vacuum nipple, screwed the bov to the hardest setting, extra-tightened the 3 bolts holding in the fuel rail [####ing overtorqued and broke the middle one], and covered the biss screw.

The result was the idle surge @ idle being 900-1.1k but still on the rage. One thing that I did notice was white smoke coming out of my exhaust during the intermittent surges. There was also a buildup of black vapor in the N1 and, as little as I could see, the piping. I wiped up as much as I could... put everything away... and went upstairs to get away.

So now, I've checked all my vacuum lines and those behind the intake manifold are still connected. My vacuum at idle reads ~18inHG so that's good. Is it possible that one of my gaskets have blown? Am I burning oil? How can I check if my bov's diaphragm has taken a shit on me? Sorry for all the questions, but I'm kind of upset like you guys as well. I don't feel it's worth driving her until it's fixed especially w/ the ~15MPG I'm getting...

Lastly, @ WOT, I can't get passed 3k in 3rd gear and up w/o the car tugging REALLY hard. It's as if it's choking. Looking forward to some responses =]

 

[super97gst]

every time i crank mine up to move it out of the way and it goes crapola on me i notice white smoke coming out of my exhaust. i also have black soot all over the inside of my greddy evo 2. what does that mean?? that would mean a lean condition, right? my a/f guage was reading so lean the day all this happened it wouldnt even show until i got it up past 2k.

 

[Artago]

Ok I think I should have specified regarding the rear O2. The rear O2 code has been there ever since I bought the car (LONG before the P0300). I have a rear O2 sensor but the wiring is messed. See this thread I started:

http://www.dsmtuners.com/forums/tuning-engine-management/275854-bad-sensor-wiring-p0136.html

My car also smoke but only when it's cold. Once it warms up it's good. However it only started smoking about a month or 2 after the P0300. Think I damaged a piston ring with the misfire?

Regarding the rear O2 code, I don't see how that's related but at this point I'm willing to try anything.

So here's what I'll do.

This weekend I'm going to get a compressor and fix all the boost and Vac leaks (should have done this a long time ago). I'll check the injectors, ignition coils (again), CAS and anything else I can get my hands on. Then I'll fix the rear O2 wiring. Then I'll get a new fuel pressure solenoid and install it. I was also planning to do a EGR block of and see if that helps.

I'll post back once all this is done.

Tom

Anyways, I just got a reply from JNZtuning regarding the Fuel pressure solenoid. They say they have one, and I'm just waiting to hear back on the price.

 

[voodoogsx]

Ok I think I should have specified regarding the rear O2. The rear O2 code has been there ever since I bought the car (LONG before the P0300). I have a rear O2 sensor but the wiring is messed. See this thread I started:

http://www.dsmtuners.com/forums/tuning-engine-management/275854-bad-sensor-wiring-p0136.html

My car also smoke but only when it's cold. Once it warms up it's good. However it only started smoking about a month or 2 after the P0300. Think I damaged a piston ring with the misfire?

Now you are sure that the smoke isn't condensation? most cars do this in the morning, mine does too. usually you'll see some droplets of water popping out of the tailpipe along with some moisture around the outlet.

Have you done a leakdown test or compression test....I don't recall it being mentioned or not at this point.

have you tested voltage for the o2 sensor to make sure the ecu is getting some sort of reading?

 

[Artago]

Now you are sure that the smoke isn't condensation? most cars do this in the morning, mine does too. usually you'll see some droplets of water popping out of the tailpipe along with some moisture around the outlet.

Have you done a leakdown test or compression test....I don't recall it being mentioned or not at this point.

have you tested voltage for the o2 sensor to make sure the ecu is getting some sort of reading?

I do have condensation because there is water coming out the exhaust but I'm pretty sure it's burning oil as well because the smoke is blue.

I plan to do a compression test soon. I hope it's good because it's a brand new motor.

The ECU is getting voltage for the front O2 (A/F gauge and Pocketlogger confirm this) but I'm getting no voltage for the rear O2 according to pocketlogger.

Tom

 

[Artago]

So I got a response from JNZtuning. They have the fuel pressure solenoid. Part #MD113721 for $51.31. The dealer wanted $140.

JNZ FTW!

Tom

 

[super97gst]

So I got a response from JNZtuning. They have the fuel pressure solenoid. Part #MD113721 for $51.31. The dealer wanted $140.

JNZ FTW!

Tom

writing that down in my parts book right now, just in case i need another one.

 

[bboyalan]

So a few days later, I have another update:

One of the saddest days for a tuner I managed to have extra funds from my two part-time jobs this week. Yesterday, after work and my one lecture class, I decided on getting a car diagnostics done. Ran a quick search and found a reputable shop here in Chula Vista on Broadway [Bowlin's Auto Service]. I brought the car over for a quoted $75 and let them see what was up. They told me that my timing was off by 1 tooth and quoted me an additional $285 for them to redo it. I called my dad up and we decided on just bringing it home to redo ourselves - yes, I wasted $75 on something that should've been done right the first time....

This morning we quickly wrapped everything up and all looked good. Started her up with confidence only to be exposed to this harsh KNOCKing sound. My heart sank and I continued letting her idle a bit hoping it was just some awkward extreme case of the already present lifter tick. The sound only worsened and I didn't know how to feel. My parents witnessed my disappointment and frustration as I simply put everything away... My mom just told me to have it fixed then sell it, but I know it's not practical being that this is a beautiful 13-year-old car w/ a salvaged title approaching 141k.

My only last thoughts were back on driving it while misfiring and off by one tooth... could putting it back into spec after all this time make the prolonged damage just evident now?? I'm trying to explore my options if this really is rod knock, twisted valves, or some other sort of damage.

~AL

 

[super97gst]

So a few days later, I have another update:

One of the saddest days for a tuner I managed to have extra funds from my two part-time jobs this week. Yesterday, after work and my one lecture class, I decided on getting a car diagnostics done. Ran a quick search and found a reputable shop here in Chula Vista on Broadway [Bowlin's Auto Service]. I brought the car over for a quoted $75 and let them see what was up. They told me that my timing was off by 1 tooth and quoted me an additional $285 for them to redo it. I called my dad up and we decided on just bringing it home to redo ourselves - yes, I wasted $75 on something that should've been done right the first time....

This morning we quickly wrapped everything up and all looked good. Started her up with confidence only to be exposed to this harsh KNOCKing sound. My heart sank and I continued letting her idle a bit hoping it was just some awkward extreme case of the already present lifter tick. The sound only worsened and I didn't know how to feel. My parents witnessed my disappointment and frustration as I simply put everything away... My mom just told me to have it fixed then sell it, but I know it's not practical being that this is a beautiful 13-year-old car w/ a salvaged title approaching 141k.

My only last thoughts were back on driving it while misfiring and off by one tooth... could putting it back into spec after all this time make the prolonged damage just evident now?? I'm trying to explore my options if this really is rod knock, twisted valves, or some other sort of damage.

~AL

i think i might be able to make you feel a lot better. think about this for a minute, both of our cars are doing basically the same thing. i dont know about yours but when all this started on mine it was intermittent. i was sitting in the car messing with the boost controller and i put it in reverse and as soon as i let off on the clutch the rpm's dropped from 1k or so to 100. i parked it, shut it off and left it. i went back out the next day and cranked it and it was fine, nothing wrong at all. 3 days later it was all back again and it hasn't stopped since. but i also haven't tried to drive the car since, and that was over 2 months ago.

i'm not saying the t-belt didn't jump a tooth on yours, because it very well could have. but since our symptoms are almost exactly the same i would think we most likely have the same problem. a t-belt doesn't jump off time 1 tooth then jump back the next day. the t-belt jumping a tooth can't possibly be intermittent, it would happen and it would stay like that until fixed. i'm fixing to go mess with mine right now, who knows, maybe i'll get lucky and find something. i thought you checked the timing on yours when all of this started?? if so you either checked the timing incorrectly or it isn't out of time. which would mean the timing belt hasn't jumped a tooth. i'll check the timing on mine as well right now. i'll post back in a few hours and let you know what i come up with. i know you feel like s*it right now, i felt the same way every time i bought new parts and it did nothing. but we'll figure it out.

 

[Artago]

My parents and friends have all told me to sell me car for a while now and buy a new car. I told them the same thing I tell everyone else.

I love the car. Despite the fact that it hasn't run right EVER since the day I got it, I still love it. DSM 4 life.

Tom