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Formula 2.8L misfiring , need advice by robert1234
Started on: 09-24-2017 04:10 PM
Replies: 16 (314 views)
Last post by: robert1234 on 09-30-2017 06:45 PM
robert1234
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Report this Post09-24-2017 04:10 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
What else needs changed ?
I've changed:
All plugs
Plug wires
Distributor and cap

I have not changed the TPS yet....

What else would need checked or changed.

Thanks


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tshark
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Report this Post09-24-2017 05:32 PM Click Here to See the Profile for tsharkSend a Private Message to tsharkEdit/Delete MessageReply w/QuoteDirect Link to This Post
You need to check spark on each wire. You could have an issue with the rotor.

If all wires are getting spark, you need to check which cylinder isn't firing, by looking at the plugs.

Were these parts replaced before or after the misfiring started? You don't have the timing off, or the plug wires out of order, do you?

The timing chain may have jumped a tooth. The ICM or coil could have issues, or the connecting cable may have issues. An injector could be sticking.

Before you throw a bunch of parts at it, you need to determine what is actually happening.
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fierofrenzy
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Report this Post09-24-2017 09:37 PM Click Here to See the Profile for fierofrenzyClick Here to Email fierofrenzySend a Private Message to fierofrenzyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Was the misfire before the tune up, or did it result after you installed all those items.
Could your Ignition Control Module be on the blink?
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robert1234
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Report this Post09-24-2017 09:44 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
It was there before the tune up. No the plug wires are in the correct order. Timing is not off. I checked that after the distributor.
It seems to be random. But it needed parts replaced anyway.
So, I guess I start checking one wire at a time. It may not be random.
I'll work on it again Monday night after work I guess.
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Gall757
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Report this Post09-25-2017 10:07 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Connectors and wiring on a 30 year old car can get troublesome. I would clean the contacts esp. on those connectors into the ICM. The whole distributor is new?

[This message has been edited by Gall757 (edited 09-25-2017).]

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robert1234
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Report this Post09-25-2017 07:37 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, the whole distributor is new. I'll check ICM connections later this week.

I just checked all spark plug wires for firing.

I also checked the 5V reference and the signal coming out of the TPS, it working perfectly. I also mapped the voltage out and there are no drop outs either.

Is it likely that my timing light has an issue and its not working correctly......it just seems to be off timing to me.

It has that rooooom, putt, roooom , putt putt sound. LOL

[This message has been edited by robert1234 (edited 09-25-2017).]

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tshark
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Report this Post09-25-2017 10:02 PM Click Here to See the Profile for tsharkSend a Private Message to tsharkEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hunting idle?
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DLCLK87GT
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Report this Post09-26-2017 09:26 AM Click Here to See the Profile for DLCLK87GTSend a Private Message to DLCLK87GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
look at it running at night, in the dark and see if there's an arc coming from the plug wires. I've seen little lightning storms coming from bad wires before and new doesn't always mean good.
New parts can be bad. Then I would check the EGR and tube. Hard to say without hearing it run. Is it a occasional misfire or is the idle searching?
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1Packrat
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Report this Post09-26-2017 09:59 AM Click Here to See the Profile for 1PackratSend a Private Message to 1PackratEdit/Delete MessageReply w/QuoteDirect Link to This Post
Pull your plugs out one at a time and rotate the plug and look for a powder burn on the top porcelain indicating a cracked plug. One of the plugs may have been cracked during install. This will happen most times installing the plugs on the back side in the V6 where you cannot see what you are doing.

Been there done that…..
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robert1234
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Report this Post09-26-2017 04:57 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok, I'll check the plugs again and check tonight in the dark for arcs.

Thanks
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robert1234
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Report this Post09-26-2017 10:10 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
I checked all plugs again, nothing and ran the engine in total darkness to look for arcs.
Still nothing.
I'm ordering a new timing light and set timing again.

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Report this Post09-27-2017 08:22 AM Click Here to See the Profile for jmbishopClick Here to Email jmbishopSend a Private Message to jmbishopEdit/Delete MessageReply w/QuoteDirect Link to This Post
Did you set the timing with the aldl jumpered?
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Patrick
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Report this Post09-27-2017 01:58 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by robert1234:

Is it likely that my timing light has an issue and its not working correctly......it just seems to be off timing to me.


Have you checked to make sure the outer ring of your harmonic balancer hasn't spun? If it has, the timing light will be useless.

[This message has been edited by Patrick (edited 09-27-2017).]

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robert1234
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Report this Post09-27-2017 09:32 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, I jumpered it the first time.

No I don't know about the balancer. I have not checked.

I got a new light, just checked and its off timing.
So, I'll start on the timing again this weekend. Get that done for sure, then go from there.

Sometimes the smallest things can be !@#$%^&, ya know.

Thanks everyone for the help...I sure appreciate it.

[This message has been edited by robert1234 (edited 09-27-2017).]

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robert1234
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Report this Post09-29-2017 08:11 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
Got a new timing light, while getting ready to set the timing, I dropped it on the driveway and now it does not work.....grrrrr.

My luck as always !

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theogre
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Report this Post09-30-2017 12:11 AM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
V6 misfire could be injector problems too... Iffy injector or wires to it.

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robert1234
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Report this Post09-30-2017 06:45 PM Click Here to See the Profile for robert1234Click Here to Email robert1234Send a Private Message to robert1234Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok, I put a new coil on and set timing correctly, really helped alot.

I think you are correct, I think the injectors are shot...
It still misfires, but not as bad as before....but still not right.
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