At my wits end with Misfires HELP!
05-28-2019, 02:57 PM
#1
At my wits end with Misfires HELP!
The problem:
Any insight would be greatly appreciated. Of the next steps list, what is greatest priority in your opinion? Are there others I am missing?
I'm trying to avoid going into a shop & tell them I don't know what the issue is, as their eyes turn into dollar signs.
UPDATE: I'm trying to get you guys the specific codes(P####) but I've been on several rides & have been unable to get a CEL. There is something wrong tho, & the main issue is bog. Step on it at like 5k in any gear & it bogs. I did live data on my OBDII reader & MAP & TPS% seem to be in normal ranges based on other threads I've read. Although supposedly that doesn't mean much. Should I multi-meter the sensors? MAP is not a big deal to replace but i'd hate to do it & have it fix nothing. Could there be a vacuum leak with all of the work I have done? Could my valve adjustment not be correct & cause this?
UPDATE #2: Replaced MAP sensor but no change. Getting the dreaded P1399 code along with the misfires in all cylinders. Upon further research I'm going to send the injectors to get untrasonic cleaning along with a before & after report. Just to rule that out. Seems like that was the issue with most who experienced that code. If that does not work, next will be TPS & a full cleaning of Throttle Body & Intake system.
UPDATE #3: Injectors went off for ultrasonic cleaning. Jim@injectorrepair.com - He's been great. Anyway...they tested horribly out of the box & then after an exterior cleaning & degreasing, tested at a 36% flow balance which apparently is horrible. According to him a flow balance at or below 5% is necessary for good performance. There was no noticeable debris, deposits, or residue inside the injectors. After two ultrasonic cleanings, only two of the injectors had flow rates between 81 - 84 cc.s, but the other two had rates of 60 - 84 cc.s. He believed they could be pitted from ethanol corrosion. He was kind enough to refund me half the money as he couldn't fix them. I've ordered another set of OEM injectors(by OEM obviously they are lifted of a wrecked s2000 or something because the parts are no longer made). Going to install these & hope they are good out of box. If not, send them to Jim to have the same cleaning done & go from there. This has been a real PITA, but at least I know what my problem is. At least I have now two good injectors lol.
UPDATE #4: 3 of the 4 OE injectors I sent out for cleaning weren't terrible. He was able to get 7% flow balance on 3 (as we know my two good ones have 5%). He claims that for a 4 cylinder engine like this he doesn't like to see anything more than 3%. I sent back to the 2 good injectors(5 percenters)...so that he could run those side by side with the 7% ones. Apparently, outside temperature, humidity, etc come into play. NOTE: This is at no extra charge, he has been a real stand up guy. Even if the 3 test at 7% & the 2 I sent back test at 5%...I will have him send them all back to me. My thinking is, if the car ran(albeit terribly) with injectors he said were "horrific"...then I have to imagine these injectors, while not perfect, will have the car running much smoother. UGH this has been a nightmare.
- After cold start, extreme bog in all gears at low rpm, but rides fine above 5k rpm (bog gets better as car warms up but is still existent)
- After cold start, misfire code will be thrown(Misfire in 1,2,3,4 & random misfire)
- Replaced spark plugs about a thousand miles ago
- Replaced coil packs several hundred miles ago
- Installed OEM fuel injectors from ebay & the bog got worse
- Used tool to flush carb cleaner through original injectors & the spray looked normal. Reinstalled but problem remained, although not as bad(misfire codes still occur)
- Done full fuel system cleaner in the gas tank
- Did valve adjustment
- replaced fuel filter
- MAP sensor
- FPR
- TPS
- Fuel Pump
Any insight would be greatly appreciated. Of the next steps list, what is greatest priority in your opinion? Are there others I am missing?
I'm trying to avoid going into a shop & tell them I don't know what the issue is, as their eyes turn into dollar signs.
UPDATE: I'm trying to get you guys the specific codes(P####) but I've been on several rides & have been unable to get a CEL. There is something wrong tho, & the main issue is bog. Step on it at like 5k in any gear & it bogs. I did live data on my OBDII reader & MAP & TPS% seem to be in normal ranges based on other threads I've read. Although supposedly that doesn't mean much. Should I multi-meter the sensors? MAP is not a big deal to replace but i'd hate to do it & have it fix nothing. Could there be a vacuum leak with all of the work I have done? Could my valve adjustment not be correct & cause this?
UPDATE #2: Replaced MAP sensor but no change. Getting the dreaded P1399 code along with the misfires in all cylinders. Upon further research I'm going to send the injectors to get untrasonic cleaning along with a before & after report. Just to rule that out. Seems like that was the issue with most who experienced that code. If that does not work, next will be TPS & a full cleaning of Throttle Body & Intake system.
UPDATE #3: Injectors went off for ultrasonic cleaning. Jim@injectorrepair.com - He's been great. Anyway...they tested horribly out of the box & then after an exterior cleaning & degreasing, tested at a 36% flow balance which apparently is horrible. According to him a flow balance at or below 5% is necessary for good performance. There was no noticeable debris, deposits, or residue inside the injectors. After two ultrasonic cleanings, only two of the injectors had flow rates between 81 - 84 cc.s, but the other two had rates of 60 - 84 cc.s. He believed they could be pitted from ethanol corrosion. He was kind enough to refund me half the money as he couldn't fix them. I've ordered another set of OEM injectors(by OEM obviously they are lifted of a wrecked s2000 or something because the parts are no longer made). Going to install these & hope they are good out of box. If not, send them to Jim to have the same cleaning done & go from there. This has been a real PITA, but at least I know what my problem is. At least I have now two good injectors lol.
UPDATE #4: 3 of the 4 OE injectors I sent out for cleaning weren't terrible. He was able to get 7% flow balance on 3 (as we know my two good ones have 5%). He claims that for a 4 cylinder engine like this he doesn't like to see anything more than 3%. I sent back to the 2 good injectors(5 percenters)...so that he could run those side by side with the 7% ones. Apparently, outside temperature, humidity, etc come into play. NOTE: This is at no extra charge, he has been a real stand up guy. Even if the 3 test at 7% & the 2 I sent back test at 5%...I will have him send them all back to me. My thinking is, if the car ran(albeit terribly) with injectors he said were "horrific"...then I have to imagine these injectors, while not perfect, will have the car running much smoother. UGH this has been a nightmare.
Last edited by project2k4; 06-01-2019 at 04:22 PM. Reason: Updates
05-28-2019, 03:40 PM
#2
Site Moderator
What year is the car? Have you checked/cleaned the sensors? I think the map sensor along with the tps sensor can be causes. Maybe look into having a compression test done?
05-29-2019, 05:05 AM
#5
UPDATE: I cleaned the sensors & haven't been able to replicate the misfire but the bog issue is still there. I was reading that the TPS can't just be replaced, you need to replace the throttle body. Am I wrong on this? Looking at the TPS the bolts don't look like they come off.
Last edited by project2k4; 06-01-2019 at 04:28 PM. Reason: update
05-29-2019, 05:15 AM
#6
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06-01-2019, 04:24 PM
#8
When you had the bad MAP sensor did you happen to run live data while driving & look at what the MAP was reading during various throttle inputs? I did this & it looked normal. It could still possibly be bad.
06-01-2019, 04:29 PM
#9
06-01-2019, 10:22 PM
#10
Car is an 04. Did map sensor whack & zip tied it in place. I have not taken the sensors off or cleaned them. I will do this next, since it is simple. Anything I should look for in knowing they may need to be replaced?
UPDATE: I cleaned the sensors & haven't been able to replicate the misfire but the bog issue is still there. I was reading that the TPS can't just be replaced, you need to replace the throttle body. Am I wrong on this? Looking at the TPS the bolts don't look like they come off.
UPDATE: I cleaned the sensors & haven't been able to replicate the misfire but the bog issue is still there. I was reading that the TPS can't just be replaced, you need to replace the throttle body. Am I wrong on this? Looking at the TPS the bolts don't look like they come off.
TPS sensor can be replaced no problem. You just need to dremel a slot into them and they come right out with a flathead.