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Multiple misfire codes

I'll look at the plugs tomorrow as a first defense. The car is going to Ramon Tuesday for a replacement of the fuel pump, battery cable and i'll let him swap some O2 sensors while the car is in the air. I'll keep you all posted as to progress. Thanks for all the suggestions.
 
If you have an analog volt meter you can check the output voltage to make sure it is in spec but I think it is usually the heater that goes on them.

If you just had the motor freshened it probably isn't the head gasket.
 
If it were me I would pull the plugs on those 3 cylinders and look at the condition. The porcelain should be a light tan color. If the plugs look good I would try replacing the o2 sensors for that bank. You can get the denso brand sensors on amazon cheap.

If the plugs are bright white ie. too lean, you may have a headgasket isssue.

Porcelain? I think you mean electrode right?

And for the op you should really change the plugs they are a very important link in the chain and the cheapest as well.
 
Thanks biscuits for jumping in. I dropped the car with Ramon and told him to fix it. We talked and he was a bit perplexed as well. But did give me some insight as to why all the codes on only one bank. I had removed all of my injectors to lend to a fellow Primer who needed to get his car home for an FI upgrade. Upon reinstalling them, I may not have tightened a connector to an injector tight enough. If there is a slight interruption in electrical flow to ANY cylinder in a bank, the codes will through for All cylinders in that bank. Here is to hoping that Ramon finds me light fingered in electrical connections.
 
EdinKali is correct about the porcelain vs the electrode. Well Ramon worked on the car today. Found a hesitation that he was able to clear up but the codes still remain the same. Guess I'm not as light fingered on electrical connectors as I had feared. He'll pull the plugs tomorrow and see what they say. Stay tuned....
 
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Plugs were pulled and still looked very good but as a we wanted to eliminate one more item, they were replaced as well. Cleared the codes and fired up the motor. Car ran nice and idled well and then about a minute later the CEL comes back on a and a few seconds later so did the TCS. I'm running out of things to replace here. Will take it back to Ramon next week as he has one more thing he thinks it might be. I sure hope so.
 
I would check leak down on engine, if that is good double check that the cam timing is correct. Some times when people do the timing belt in the car it is very difficult to see if the rear cylinder head cam timing is correct. I would also check the valve adjustment I would check the car with the factory scan tool as it gives you information way beyond what a generic scan tool will give you. We have this tool at our shop it was 5k so we like to use it a lot. also I would check your exhaust system as well you could have something that is coming apart and blocking the flow of exhaust. With having misfire only on the rear cylinder head this indicates that something is mechanically wrong with the engine. If the misfires were all over the place I would think electronics. Hope this helps.

Mike@AutoWave Inc.
 
Thanks Mike. I 'm pretty sure this is what Ramon had planned. Shad at DA rebuilt the whole motor not even a year ago. Can the timing belt skip a tooth on the cam that easy? Thanks for the advice. I'll keep you all posted.
 
Update time. Ramon pulled the plugs and did a leak down and compression check. All good and the compression is 175 on each cylinder (thanks Shad, nice job). Plugs looked good so back in they went. Timing is dead on balls perfect so no issue there. Adjusted all the valves again. They were done not 4k miles ago. Found a loose ground on a box on the passanger side of the engine compartment. Pictures attached. Tightened it down. Fired up the car and the codes came back, all of them. Ramon disconnected the connector for what ever this box is (doesn't show it in the NA2 Service Manual so I have no idea what it is) and the same code were still there.

So I'm kind of left with what I think are my only options left.

  1. It could be the loom that contains all the injector connectors from the ignitor on top of the intake plenum.
  2. It could be a bad ECU.
The car does not hesitate and it runs real strong. Running out of options here. Any more thoughts?
 
Update time. Ramon pulled the plugs and did a leak down and compression check. All good and the compression is 175 on each cylinder (thanks Shad, nice job). Plugs looked good so back in they went. Timing is dead on balls perfect so no issue there. Adjusted all the valves again. They were done not 4k miles ago. Found a loose ground on a box on the passanger side of the engine compartment. Pictures attached. Tightened it down. Fired up the car and the codes came back, all of them. Ramon disconnected the connector for what ever this box is (doesn't show it in the NA2 Service Manual so I have no idea what it is) and the same code were still there.

So I'm kind of left with what I think are my only options left.

  1. It could be the loom that contains all the injector connectors from the ignitor on top of the intake plenum.
  2. It could be a bad ECU.
The car does not hesitate and it runs real strong. Running out of options here. Any more thoughts?

I believe that's the ignitor if I'm not mistaken... I'm having the same issues, car run strong but getting codes. I'm trying the 02 sensors next.
 
Are there two (2) freakin' ignitors? I've heard of redundancy but that is strait our of the "Department of Redundancy Department":eek:
 
Are there two (2) freakin' ignitors? I've heard of redundancy but that is strait our of the "Department of Redundancy Department":eek:

no its is the spark plug detection module, my 97 had cel with codes ,p1316 (bank 2) ,p1317 (bank 1) . there are two small ground wires that come out of the top harness plug and ground to the module bracket . mine were broken at the ground connector ,car ran fine just had light and codes. ,
 
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I went through this same problem in my S2000. I replaced everything like mentioned in this thread. In the end my loss motion assemblies were bad. Some were sticking. Its worth a shot. I also have had the same codes inmy Nsx and the tct light also came on which I found strange. My cel was from my tune.
 
your picture #2 , to the right of the top module plug ,ground bolt with a double wire eye crimp. check carefully ,

That was the loose ground that was found and reconnected. Still threw codes after reattaching. Pulled that top connector after we cleared the codes and all five popped up again immediatley. I'm going to pull that bugger apart and see if there is something not connecting or needing to be cleaned up.

As to the possible off tune or LMA issue, the car is completely tuned and the LMA's were not only replaced but upgraded when the motor was rebuilt last Spring by Shad at Driving Ambition. I doubt it's them. But the Spark Plug Module......

I'll keep you all posted.
 
I don't believe that is a stock ground location for that eye crimp. It's a horrible way to pick up ground especially on our Aluminum cars. Try to scuff up the paint below it on the frame and at least pinch the eye crimp between the chassis and the bracket. Try relocating the ground first. Seems like something easy to try out. Better yet, find a proper dedicated ground for it on the chassis with it's own dedicated bolt.

I had codes recently and it was because the ground on my igniter was below par. I scuffed up the paint to promote better contact and problem solved.
 
I don't believe that is a stock ground location for that eye crimp. It's a horrible way to pick up ground especially on our Aluminum cars. Try to scuff up the paint below it on the frame and at least pinch the eye crimp between the chassis and the bracket. Try relocating the ground first. Seems like something easy to try out. Better yet, find a proper dedicated ground for it on the chassis with it's own dedicated bolt.

I had codes recently and it was because the ground on my igniter was below par. I scuffed up the paint to promote better contact and problem solved.

No that is the stock location , make sure bracket and crimp are clean and tight .
 
Thanks for clarifying. It was a long shot.

I agree with you ,when I had the cel come on and checked the codes, these are not popular codes . I found the broken wires and repaired them ,cleared the codes and problem solved . Then I thought ,look at this the grounds are made by a eyelet ,bolted to a bracket that is dependant on a bolt to the car . too many connections that can screw up :confused:
 
Well I pulled the module out and cleaned all the connectors. I disconnected the ground with the two black wires. Looked it all over and the wires looked good so I connected the ground upside down so it would make more contact. Plugged them back in and guess what? All five codes are still with me. I thought I might be able to flip this module around and plug it in 180 degrees out but it is not made universal on the plugs. Of course not, what was I thinking?

Now I've developed a serious gas leak at the filter since upgrading the fuel pump so I can't even turn the car on to check for codes unless i want to cover the car and garage in gas. Guess I'll get some new crush washer and go Neanderthal on this bad boy tomorrow. Man this is getting frustrating. Guess I'll be reaching out to Autowave on Monday to see if I can have Mike hook up the diagnostic machine and see what this is. Stay tuned.....
 
well i am glad you are finally giving Autowave a shot, seriously with all your problems you need to go there to get it sorted out.
 
All my problems? Since I first spotted the car and had Shad do a PPI, the car has not been that bad service wise. I had the motor completely rebuilt inclusive of all the service issues before I took possession of it. It has run great since.

The EPS went out on it and no one could fix it. I won't name names but let's just say that no one could fix it short of replacing the rack. I decided to take another route and my chronicles are well detailed in that repair. I won't say that I blazed any trails but the NSX community now has options if and when their EPS or manual racks need repair.

The misfire code issue has also seen the inside of many shops we all use and recommend. All to no avail. I have also documented my thoughts, fixes and follies so that other Primers who want to work on their cars (some of us like to) can fix their own car when this sort of thing happens.

Mike stated in this thread that he has a wonder machine that can detect anything. As a last resort, I'll take it there and see what they find. I will document that too.

This is not a "whose better" ending. We have not written the last chapter. We'll wait and see.

I really don't feel like I have that many problems. Well, only 290 rwhp on a NA '97 maybe...
 
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