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Old 06-18-2008, 03:35 PM   #1
Richardcranium419
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Default Mis firing under any load

Mis firing under any load
I did a search and did not find anything that had the same sort of problem.

After the built motor install (Axis Stage 4) on the first drive. I am having a misfire hesitation. And to make it worse My code reader will not connect. (it plugs in just will not talk to the ECU. So I have no idea which cylinder it is misfiring on if not on all of them.

Idle is fine, and revs fine in neutral.
When in gear and under load it miss-firs and hesitates bad.
I will be installing a new set of plugs. It may have fouled a plug when I started the motor for the first time and it would not idle. That issue turned out to be a cam sensor not being plugged in. (I must of missed it when I did the install.
When installing the new plugs I will check all the coil connections, and make sure they are seated properly.

Is there any way to check the coils to make sure they are working right?

Is there anything else I should check if that does not fix the problem?

Thanks for any information.

Mods as it sits right now.
Engine
Axis Stage 4 Components:
2.35 Liter Fully Closed Deck Short block (EJ22t
Piston Squirters
Stock Steel Sleeve Liners
Modified Axis Racing Forged Crankshaft
Balanced & Polished to 10,000 RPMS
Pauter 4340 Chrome-Moly Forged Rods
Axis Racing/ CP forged pistons (8.5:1 or 9:1)
8500 RPM Rev Limit

Downpipe and Straight catless midpipe (Perrin)
Stealth Exhaust Midpipe (TurboXS)
ARP head studs
Motor mounts (Group-N)
TGV deletes
Axleback exhaust (ProDrive)
Front Mount Intercooler

UTEC/Tuner (TurboXS) w/ custom tune[FONT='Arial','sans-serif']

Turbo XS BOV RFL
Battery (Odyssey 680 MJ)
Light Weight Crank pulley (Perrin)
One step colder plugs (NGK LFR7AIX)
Head gaskets (Cometic Head gasket)


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Old 06-18-2008, 04:39 PM   #2
benw
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knock sensor installed and torqued correctly?
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Old 06-18-2008, 04:53 PM   #3
Richardcranium419
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Yes one of the first things I checked. I thought that may have been pulling timing.
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Old 06-18-2008, 05:16 PM   #4
wgknestrick
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Pull the plug and find out which one is misfiring by reading the plugs, then compression test that cylinder(s). Then double check all the engine harness grounds for resistance to chasis ground. IME they are more suspect than the coils actually failing.

I have the same plugs as you and have problems with misfires like you. I don't think the STIs like to run them regardless of setup. Stick with the -11 stock heat ranges.
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Old 06-19-2008, 09:09 AM   #5
Richardcranium419
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Changed the plugs, they did not look bad. (Just alittle dark) made sure the coils were seated right and checked all the grounds again. Still hesitates...

Ran some UTEC logs, I will post them up in a few.
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Old 06-23-2008, 02:35 PM   #6
Richardcranium419
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Here is my misfire Log. As you can see Under the RPMs it is showing some crazy numbers. jumps from 2800 something to 10,000 something back down to 28 or 2900 something.

It looks like the ECU is getting bad info from somewhere. Any ideas? I think it may be the Crank Sensor.

It is misfireing on throttle under load. Cold idle is good, but after warm up and a short drive will not hold idle at all. Stalls with no throttle.

Can you see any other things in this log that look out of place?




http://www.thesuicidaleggroll.com/ho...ew_block_5.txt
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Old 06-23-2008, 03:54 PM   #7
jaxscuby
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check crank sensor.
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Old 06-24-2008, 08:38 AM   #8
Richardcranium419
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Changed out the Sensor. It did not work. Now I do not know what to do.
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Old 06-24-2008, 09:55 AM   #9
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I used to use those 1 step colder plugs too, but was getting misfires with them. I'd recommend using the stock ones unless you absolutely need the colder ones. Just remember they HAVE to be gapped manually to .028"-.030". They come gapped around .040" which is too large for a turbo car.

Did you ever measure your harness ground resistances, and not just continuity? The driver's side manifold ground has a ton of sensors going to it. It probably wouldn't be a wasted effort to make a cheap grounding harness to go from each side of the chassis to both manifold grounds, and the crank sensor bolt. This would guarantee a good ground for all the sensors involved.

The Utec is also known to burn up coilpacks.

Has the motor ever run right since it was built? You may have have the timing off or a compression problem.

Was the new engine ever tuned? Ignition timing problems could be causing the misfire if your engine is drastically different from what was it was tuned for.
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Old 06-24-2008, 10:48 AM   #10
Richardcranium419
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When I changed the plugs I went back to stock. Still same problem.
I can measure the resistance tonight.
I am still running the stock heads, what I changed was from a 2.5 to a 2.35.
The motor has not ran right sense the build. It will more then likly show low compression sense the new block only has about 10 miles on it. Right?
I will make some small changes to the timing and see what happens.
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Old 06-24-2008, 11:09 AM   #11
wgknestrick
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What compression is it showing? I have a hunch that the block itself is causing the misfires (probably not what you wanted to hear). You might have a timing issue.
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Old 06-24-2008, 11:21 AM   #12
charliew
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Are you real sure the crank and cam sensor gap to the wheel "humps" is close enough for a good signal?
One of these threads had a good outcome with closing the gap for a stronger signal. If the feedback from the sensor is erratic it must be fixed.

Most likely your problem can't be fixed by anyone unless you get the code reader working and you know for sure what feedback the ecu isn't getting reliably.

Last edited by charliew; 06-24-2008 at 11:29 AM.
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Old 06-24-2008, 11:35 AM   #13
Richardcranium419
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I have some one comming over with a diff code reader. So I will try that out.

Or I may try to keep it running by keeping revs up when comming to a stop. And head to Vatozone.
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Old 06-24-2008, 12:48 PM   #14
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have you tried without the utec?
Maybe reflashing the factory ecu would help you troubleshoot. The problem could be the utec. Not the first time a utec has caused problems either.
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Old 06-24-2008, 01:32 PM   #15
Richardcranium419
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It could be the Utec. But the Utec was in the car before the motor build. And was not touched during the build at all.
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Old 06-24-2008, 02:32 PM   #16
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Quote:
Originally Posted by wgknestrick View Post
What compression is it showing? I have a hunch that the block itself is causing the misfires (probably not what you wanted to hear). You might have a timing issue.
Once again.....
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Old 06-24-2008, 03:36 PM   #17
Richardcranium419
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I have not checked the compression on the new motor. From what I understand it will be bad, due to the rings not being seated yet. Only ten miles on new block.

If I am wrong, and you can tell something by the numbers I will do a check.
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Old 06-24-2008, 05:54 PM   #18
wgknestrick
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A compression test will still provide information to you. Compression will surely go up as the engine breaks in, but it should still be "there" from day one. I always test my engines before they even are put back in the car as it is a good sanity check. I suspect you have a cam out of time and this should show on a compression test. 10 cranks cold.
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Old 06-25-2008, 08:39 AM   #19
Richardcranium419
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I will check the compression tonight. I had to work late last night and did not get a chance to do it. If A cam is out of time. Then one side will be lower comp then the other right?
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Old 06-25-2008, 08:55 PM   #20
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Check to make sure that your map sensor is calibrated correctly. Your car is doing the same thing that mine was doing at the Mile last October.
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Old 06-26-2008, 08:29 AM   #21
Richardcranium419
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I am useing the same map sensor as the stock block. Is there any reason it would change?

And to make it even harder to find the issue. I was able to pull the codes last night. And there were no misfire codes. I did not have the time to do the compression check last night. I had to teach a class at church. I should have time to do it tonight.

Also if I disconected the UTEC and ran on the stock ECU. It would run bad but if it does not have the hesitation, that would mean it was the UTEC right?
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Old 06-26-2008, 07:56 PM   #22
Richardcranium419
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just got done with the compression test. and I still do not have an answer.
1. 115
2. 115
3. 115
4. 120

motor only has 143 miles on it.
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Old 06-27-2008, 02:18 AM   #23
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you should allow 10 psi per cylinder variance. comp test looks ok i guess, should be around 140 ish but with new rings could be the culprit as far as lower comp test results. what injectors are you running?? coils ok?? timing belt ok??? i dunno what else just guessing
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Old 06-27-2008, 08:40 AM   #24
Richardcranium419
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Stock injectors
coils tested ok
timing belt s brand new

I think I will start changing out some fuel items and see if it changes. Like fuel pump and fuel filter.

I will also be installing new injectors this weekend. I got the 1000cc P & L kit.
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Old 06-27-2008, 09:47 AM   #25
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Intake leaks? Disconnected Sensor? Check the MAF? I would look at things that you have touched putting the new engine in first.
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