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-   -   Making Progress...NEED HELP!!! (https://www.miataturbo.net/general-miata-chat-9/making-progress-need-help-20304/)

NAshowdown95 04-30-2008 01:33 AM

Making Progress...NEED HELP!!!
 
So those of you that are familiar with my other thread about my car having hesitation problems and so forth ive made some progress from where it was before. The past week it wouldnt even idle. Its a 95 for those of you that are NOT familiar.

Got it idling but its still idling rough like its not firing all cylinders. Can visually see the fuel spitting out of the tail pipe.

Pulled #1 spark plug wire-car stalls
Pulled #2 spark plug wire-car stalls
Pulled #3 spark plug wire-car does nothing.
Pulled #4 spark plug wire-Sounds like a weak spark and the car does nothing.

Replaced/Fixed:
New o2 Sensor
New wires
New plugs
MAF
Coil Pack
Put in test pipe. (eliminate clogged cat)
Swapped a 1.6 CAS in. (Been told they are interchangeable)
Run 93 octane since i got the car.
Fuel Pump is less then 2 yrs old
Fuel Filter is even newer.
Clean/Checked Grounds.

Still get very high voltage off the Igniter pin on the ECU.
WAYYYYYY above spec of .5v-1v (Getting 10-11v)
:vash:

patsmx5 04-30-2008 01:41 AM

Pull spark plug wire one and plug. Attach wire to plug. Ground plug to engine securely and spin motor over. Observe if their is hot consistent spark. Repeat for all cylinders. Then come back and tell us what spark looks like. Also, do you have the firing order correct? Post pics of said sparkplug wires installed.

J.T. 04-30-2008 02:02 AM

From the first thread it kinda sounds like #3 and #4 are switched,but you've probably tried that. That is some AWEFULLY out of spec voltage at that pin, find a miata friend that likes you and will let you borrow and ECU for 5 minutes?

Sorry if I'm completely on the wrong train of thought, I'm used to troubleshooting neons

Fireindc 04-30-2008 02:03 AM

Make sure there is no water in your spark plug wells, and +1 on patsmx5's advice.

NAshowdown95 04-30-2008 02:08 AM


Originally Posted by patsmx5 (Post 249794)
Pull spark plug wire one and plug. Attach wire to plug. Ground plug to engine securely and spin motor over. Observe if their is hot consistent spark. Repeat for all cylinders. Then come back and tell us what spark looks like. Also, do you have the firing order correct? Post pics of said sparkplug wires installed.

Just took the car out and its running right now???
Think the it might have been something to do with the coil pack connector because it was loose as if it wasnt clipped right? idk but i wiggled with it and it fired right up and ran decent but it still hesitates when you give it hard throttle and it will surge hard in high RPMs

NAshowdown95 05-04-2008 04:51 PM

So the car doesn't hesitate and cut out anymore under lots of throttle anymore but it does seem to still act strange? I took the timing to 12 degrees and it seemed to smooth things out but i have no power on top end at all??? It wont actually pull like it used to til i get to 5k then it surges in real hard to redline but basically 3-4800k is dead in the water when pulling power is in the question??

any suggestions guys?

Mimime 05-04-2008 10:46 PM

I had similar problems like so, it was due to an Fuel Filter!!!!

patsmx5 05-04-2008 11:21 PM


Originally Posted by patsmx5 (Post 249794)
Pull spark plug wire one and plug. Attach wire to plug. Ground plug to engine securely and spin motor over. Observe if their is hot consistent spark. Repeat for all cylinders. Then come back and tell us what spark looks like. Also, do you have the firing order correct? Post pics of said sparkplug wires installed.

Do this then report back. Why are you ignoring the most sound, logical, cheap, and methodical advise you have been given? Rather than perform simple test to narrow down the possibilities, try making multiple random changes to your setup and throw parts at it, and see if that helps.

Originally Posted by NAshowdown95 (Post 251797)
So the car doesn't hesitate and cut out anymore under lots of throttle anymore but it does seem to still act strange? I took the timing to 12 degrees and it seemed to smooth things out but i have no power on top end at all??? It wont actually pull like it used to til i get to 5k then it surges in real hard to redline but basically 3-4800k is dead in the water when pulling power is in the question??

any suggestions guys?

Do you really need to end every thought with a question mark or two or three? Try periods after statements, and question marks after questions. Use some basic grammar and people will be less likely to ignore your thread.

Saml01 05-05-2008 10:43 AM

I thought there was a wire harness change in 95. Maybe the pins you are measuring for your triggers are the wrong ones?

Joe Perez 05-05-2008 11:39 AM


Originally Posted by NAshowdown95 (Post 249792)
Still get very high voltage off the Igniter pin on the ECU.
WAYYYYYY above spec of .5v-1v (Getting 10-11v)
:vash:

Real quick- by the "igniter pin on the ECU" are you referring to the brown and brown/yellow wires (ECU positions 1H and 1G for '94-early '95, uncertain for late '95, but either the same as previous, or possibly 4R and 4N as with a '96) which trigger the igniter? If so, the spec you quote of .5v-1v is wrong, or at the very least grossly misleading.

You need an oscilloscope to measure those lines, because the pulse duration is too short for any voltmeter to accurately sample. However, the correct "on" voltage is between 4 and 5 volts on a 1.6, and in the 10-12 volt range for a 1.8. It's possible that a simple voltmeter might register them as .5v-1v due to its lack of responsiveness, but this is *not* an accurate measurement.

If you're reading a steady 10-11v on either of those lines, then at a minimum you've fried a coil.

Quick question- do your coil connector have four wires or three? And when you pulled a wire, did you ground it out? If not, you killed two cylinders, instead of just one (and put some seriously undue stress on your coils).


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