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I do not.
BUT, would you care to share the year of your vehicle?

Bob.
 

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Normally, gen2 ECU's don't have problems (but it CAN happen).
Bucking....it sounds like a fuel issue to me...

Mileage? Last Maintenances?
How long has this problem been persisting?

Also, for reference,the model of your 97 might help....

Bob.
 

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Discussion Starter #6
Normally, gen2 ECU's don't have problems (but it CAN happen).
Bucking....it sounds like a fuel issue to me...

Mileage? Last Maintenances?
How long has this problem been persisting?

Also, for reference,the model of your 97 might help....

Bob.
It’s an SL with 168,000 miles and the problem started happening within the last 100 miles we’ve changed the fuel filter spark plug,all the coils, plug wire and injector when the check engine light comes on it comes up as a misfire in cylinder #3
 

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A bit of information overload....
You changed:
1) The fuel filter?
2) All 6 spark plugs?
3) All 3 coils?
4) All 6 spark plug wires?
5) All 6 injectors?
 

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Discussion Starter #8
Oh shoot sorry bout that we’ve changed
1.the fuel filter
2.only cylinder 3 plug, plug wire and injector
3.all 3 coils
 

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I am at a loss.
It seems you have used the info you have and attacked in the right way...

One last question, what transmission do you have?

Bob.
 

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Ugh.
My last though was that it was an automatic transmission issue. They have some weird symptoms....

Bucking to me (since I've been through this before with my son's VR4) sounds like a fuel issue.

I'm waiting,like you, for someone with more knowledge than me to post....

Bob.
 

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93 NA ATX 3000gt DOHC
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I suspect a DOHC engine is being discussed here, since you indicated replacing all three coils. If correct I’m wondering how ECU knows it’s #3 cylinder and #6 is not being affected. I can only imagine that somehow it’s using input from cam position sensor to determine 3 from 6. Which makes me think it might be related to cam sensor, but since I’m not familiar with all the codes available on ‘97’s I couldn’t say for sure.
 

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Discussion Starter #13
I suspect a DOHC engine is being discussed here, since you indicated replacing all three coils. If correct I’m wondering how ECU knows it’s #3 cylinder and #6 is not being affected. I can only imagine that somehow it’s using input from cam position sensor to determine 3 from 6. Which makes me think it might be related to cam sensor, but since I’m not familiar with all the codes available on ‘97’s I couldn’t say for sure.
I had bought an oem cam and crank sensor a couple months back for a different problem
 

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93 NA ATX 3000gt DOHC
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Might sound strange but I would pull top timing belt covers, start engine and watch timing belt between front and rear cam gear sets for any flapping up and down of belt between gears. Primarily interested in belt track from back intake cam and back exhaust cam for slack occurring there causing up and down motion of belt.

To offer explanation; I’m wondering if something might be causing the cam sensor to miss sending signal to ECU for it to know #3 cylinder is coming to TDC on compression stroke, which would cause it not to fire injector for that cylinder on occasions. If belt tension wasn’t correct it’s one thing I could imagine getting worse as engine heated up.
 

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Would anyone think it could be the ignition control module?
Not likely since it would also misfire #6 as well as #3. Because same coil fires both at same time, just that one is wasted spark condition depending on which one is on compression stroke.
 

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Discussion Starter #17
Might sound strange but I would pull top timing belt covers, start engine and watch timing belt between front and rear cam gear sets for any flapping up and down of belt between gears. Primarily interested in belt track from back intake cam and back exhaust cam for slack occurring there causing up and down motion of belt.

To offer explanation; I’m wondering if something might be causing the cam sensor to miss sending signal to ECU for it to know #3 cylinder is coming to TDC on compression stroke, which would cause it not to fire injector for that cylinder on occasions. If belt tension wasn’t correct it’s one thing I could imagine getting worse as engine heated up.
I’ll definitely try that I might only be able to get to that next weekend though but will for sure let you know if I see anything
 

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I’d like to add that the misfire only happens under load
In that case you might want to do compression check on that cylinder as well.
 
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