Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: Mikey97D on June 04, 2024, 08:53:14 AM

Title: Misfire - '88 TC
Post by: Mikey97D on June 04, 2024, 08:53:14 AM
My car began misfiring at idle and lower RPM's.  Revved up and in the boost it appeared as if the miss would disappear.

I started with changing the spark plugs (gap .028 to .03), new wires, cap & rotor.  Ran better, but misfire was still present.  Borrowed a smoke machine to check for vacuum leaks and nothing present.

Ran Codes:
10 System Check
11 Pass Code
14 Ignition Profile Pickup Circuit Failure (PIP)
41 O2 code for out of range or low voltage (makes sense with misfire)

I was under the impression if the PIP has a problem, starting the car becomes difficult or impossible?

Could this be simply the PIP going bad?

Side note, a week before this happened my daughter turned 16 y.o. and I was giving lessons with the 'Bird since she claims it is her's when I sell.  She needs some more lessons and how to control the gas pedal without hitting the redline.  Kinda wish i put the MSD in with the rpm limit.

(https://i.imgur.com/XTANyPxm.jpg)

(https://i.imgur.com/L70kStrm.jpg)

(https://i.imgur.com/7yNP7c9m.jpg)
Title: Re: Misfire - '88 TC
Post by: Chuck W on June 04, 2024, 09:05:43 AM
Check your distributor/aux shaft gears.

I had a set worn enough to cause a misfire at different engine speeds.

(https://turbochuckcom.ipage.com/webimages/projects/83%20TBird/2020/dist/distgearworn.jpg)
Title: Re: Misfire - '88 TC
Post by: Ductape91 on June 04, 2024, 12:36:06 PM
I was under the impression if the PIP has a problem, starting the car becomes difficult or impossible?

Restarting the warm motor does when the PIP or TFI module goes from my experience with them.
Title: Re: Misfire - '88 TC
Post by: Mikey97D on June 04, 2024, 12:51:29 PM
 :frown:
now I am scared......
will try pulling the distributor tonight.  thanks guys!
Title: Re: Misfire - '88 TC
Post by: Ductape91 on June 04, 2024, 06:32:30 PM
If it is it aint that big of a deal to replace it like people make it out to be, pulling the distributor and reinstalling it was harder than rebuilding it for me.
Title: Re: Misfire - '88 TC
Post by: Mikey97D on June 04, 2024, 06:49:41 PM
Some edges but nothing too bad on the gear.  Phew!
(https://i.imgur.com/5lrOOshm.jpg)

Now to find a PIP!
Title: Re: Misfire - '88 TC
Post by: Chuck W on June 04, 2024, 08:53:40 PM
Look down at the aux gear as well, just to verify.

Mine would drop cyl #3 at idle, but then come back when engine speed came up.
Title: Re: Misfire - '88 TC
Post by: Mikey97D on June 05, 2024, 05:46:20 PM
Look down at the aux gear as well, just to verify.

Mine would drop cyl #3 at idle, but then come back when engine speed came up.
Thanks for the heads up.

Just checked the motor side and it looks better than the distributor gear.

Tomorrow a new pip is supposed to arrive from Summit.  Had trouble finding one even listed at the local parts stores.
Title: Re: Misfire - '88 TC
Post by: Ductape91 on June 09, 2024, 03:42:11 PM
Did you get the PIP sensor?
Was it the right one?
Title: Re: Misfire - '88 TC
Post by: Mikey97D on June 10, 2024, 01:00:48 PM
Did you get the PIP sensor?
Was it the right one?
The sensor came in Friday, but I just didn't find the time to touch the car yet.  From what I can see it looks similar.
Title: Re: Misfire - '88 TC
Post by: Mikey97D on June 15, 2024, 01:09:10 PM
Finally found some free time to install the PIP.  Standard LX222 PIP fits and looks almost identical.

The idiot reinstalling the distributor gear though (me) not so good.  Minor chip on 2 teeth while driving it back on.  Don't ask.....I know better.

Where can I get this sintered gear?  Everything I see online looks questionable and made of steel.

Title: Re: Misfire - '88 TC
Post by: softtouch on June 15, 2024, 02:01:28 PM
When I did this job I put the distributer shaft in the freezer the night before and heated the gear.
I still had to tap it on, but it may have helped a little.
Title: Re: Misfire - '88 TC
Post by: Ductape91 on June 15, 2024, 05:16:50 PM
 :twocents:

I never had to do that, just some wd40 and lightly tapped it down using a deep socket. The first time i did one on my 86 tbird it was taken apart and put back together on my dining room table.
Everybody uses the same stock images for the distributor gear so its hard to tell honestly. Quick look around shows a bronze gear for 80 bucks from esslinger, the kit is over 300.
Title: Re: Misfire - '88 TC
Post by: Mikey97D on July 08, 2024, 08:17:11 AM
I got the dizzy put back together over the 4th.......and it still misses.
Used the timing light to see if each cylinder was getting spark and it flashed for each.
Ran a compression test on the first three cylinders and got 100, 50, 50 and stopped.  how can this even start with that low of pressures so I went to AutoZone to "rent" a compression tester.  Same readings to confirm my tester.  Original test were 140-150 so something is definitely up. 

Waiting for my friend's garage floor to be fixed and pull the head over there.  A/C garage sounds too good to pass up.

Title: Re: Misfire - '88 TC
Post by: Chuck W on July 08, 2024, 09:53:20 AM
Oof. :nonchalance:
Title: Re: Misfire - '88 TC
Post by: Mikey97D on July 15, 2024, 08:04:54 AM
Pulled the head off and the gasket popped between cylinder 2 & 3.

Head is back on and need to button up a few other items.
Title: Re: Misfire - '88 TC
Post by: Ductape91 on July 15, 2024, 12:24:16 PM
That sucks, especially since your spark plugs dont indicate a blown headgasket couldve been the issue.
Title: Re: Misfire - '88 TC
Post by: Tbird232ci on July 16, 2024, 07:52:28 PM
That sucks, especially since your spark plugs dont indicate a blown headgasket couldve been the issue.

It's actually pretty common. These things will blow the gasket between cylinders rather than between the cylinder and cooling jacket. The plus might just show rich, which will make you think it's an ignition problem.

Luckily, the 2.3L is pretty easy to yank the head off of. It's just heavy.
Title: Re: Misfire - '88 TC
Post by: Mikey97D on July 17, 2024, 08:08:56 AM
That sucks, especially since your spark plugs dont indicate a blown headgasket couldve been the issue.

It's actually pretty common. These things will blow the gasket between cylinders rather than between the cylinder and cooling jacket. The plus might just show rich, which will make you think it's an ignition problem.

Luckily, the 2.3L is pretty easy to yank the head off of. It's just heavy.
It actually showed lean!  I guess the wide band O2 sensor doesn't read raw fuel as rich.  It surprised me on the readings.

I used an engine hoist to lift and put the head back on!!!!  LOL