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Topic: Shuddering engine...UPDATE July,1 (Read 14868 times) previous topic - next topic

Shuddering engine...UPDATE July,1

Reply #90 –
Quote from: vinnietbird;392768
oh yes, and my car is an '88, not an '87.
The stock 88 doesn't have the fuel pump monitor wire either. It would have to have been added as part of the mass air upgrade.

You run the KOER (Key On Engine Running) the same way you ran KOEO. Instead of just turning the key on you start the car. The car should be warmed up first.

First you will get a 4, This is the engine ID code for 8 cylinders.

You may get a 1. Looks like the seperation code but here it's called the Dynamic Test code
Do a mometary wide open throttle.

It will output each code twice, just like KOEO.

After it finishes outputting codes do a momentary WOT to start the cylinder balance tests.

The test shuts off the spark and injector to each cylinder one at a time and measures how much it changes the RPM.
It will output code 10 for cyl 1, 20 for cyl 2, etc to 80 for cyl 8 or 90 for all ok.

It will then repeat the test at a different threshhold and give codes again.
Let it run until the engine shuts off.

Shuddering engine...UPDATE July,1

Reply #91 –
How do I see the codes while I'm in the car doing the WOT thing? Also, what do you mean "until the engine shuts off".
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Shuddering engine...UPDATE July,1

Reply #92 –
Quote from: vinnietbird;392773
How do I see the codes while I'm in the car doing the WOT thing? Also, what do you mean "until the engine shuts off".

The balance test takes awhile so you will have plenty of time, or you can operate the throttle under the hood. Or you can place your meter where you can see it through the windshield.
The test will turn off the engine when it is done.

Shuddering engine...UPDATE July,1

Reply #93 –
I'll give it a shot right after work tomorrow. Hopefully something positive will come of it. May end up taking it to a shop for the first time ever.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Shuddering engine...UPDATE July,1

Reply #94 –
Work? Aint nobody got time for dat!

Shuddering engine...UPDATE July,1

Reply #95 –
Quote from: Bob;392729
Is this just an anyonance or is there decreased performance and gas milage?

So which is it Vinny?
[SIGPIC][/SIGPIC]

Shuddering engine...UPDATE July,1

Reply #96 –
could this be a fuel pressure problem?  I never saw you say anything about checking the fuel pressure.

Shuddering engine...UPDATE July,1

Reply #97 –
Vinnie,

I posted a few back and inquired if you checked the MAF sensor to see if it was dirty and if so did you clean it?  My Coupe gave me all kinds of hell and it turned out this was all it was.

There is also a way to use the check engine light as your code reader:

http://www.corral.net/tech/maintenance/eecivtest.html#two

Here is the diagram for using an ohm meter or a test light:



Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Shuddering engine...UPDATE July,1

Reply #98 –
Fuel pressure should be checked. But he replaced the PUMP!!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Shuddering engine...UPDATE July,1

Reply #99 –
Vinne,

Koer means Key On Engine Running
Koeo means Key On Engine Off
Cm means Continous Memory.

Everything here was explained in that sbftech like I posted on page 1.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Shuddering engine...UPDATE July,1

Reply #100 –
It is a performance issue, Not running as it should.

It's an annoyance, and I haven't put enough miles on it to tell if it's effecting the mileage. It did pop twice yesterday through the tailpipe. I don't have a fuel pressure gauge, and Autozone's didn't work. There was a nice strong spray when I pushed the schrader valve, but that doesn't mean anything. I'll do the KOER test after work. Very strange issues..
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Shuddering engine...UPDATE July,1

Reply #101 –
If you have a dirty MAF, the PCM will go rich at idle and low rpm, because the crud on the hot wire will act as a heat sink, making the PCM think that more air is flowing over it than there is.  Once you add some RPM's, however, the crud in the MAF acts as an insulator, causing the PCM to think that there is LESS airflow than there is.  The MAF is the only component that can do this.  It may not be the problem, but it should certainly be clean.  MAF is the NUMBER ONE component in the fuel calculation.  Also, you haven't mentioned anything about checking for unmetered air.  Is the plumbing tight and leak free between the MAF and the TB?  A speed density system wouldn't care, but a MAF system won't tolerate it.  And in the search for unmetered air, you'll want to check for vacuum leaks and a stuck PCV valve. 
Beyond that, have you tested the MAF as a component by unplugging it with the key off, then starting and driving it?  If the MAF is the problem, your shudder would be gone with it disconnected.  I should add that our driveability guy has a 5 gallon bucket of bad MAF's sitting under his bench, so it's not exactly uncommon.

Shuddering engine...UPDATE July,1

Reply #102 –
KOER test done. Code 33 and 91.

33 being EGR issue (I don't have an EGR on my car)...never had an issue as far as performance or anything else from that for years.

91 states that it is an EGO sensor  problem due to pressure or injectors out of balance.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Shuddering engine...UPDATE July,1

Reply #103 –
Code 91 is lean hego sensor left side

http://oldfuelinjection.com/?p=48

Use this to referance codes. The books are generic, ford fuel injection uses codes for mustang and trucks.

Try uplugging your o2's and see if the miss goes away.

You can also do a cylinder ballance test, as described in the sbftech link on the first page. If its an injector problem, it should pick it up and id the cylinder for you so you only have to swap the one. How it works, it raises the cars idle to about 2000 rpm to keep the engine running, then it turns off and sprays each injector individially, noting the change in engine rpm's. You can run the test 3 times. Code 9 means pass. If you pass it the first a second time, your injectors are working correctly. The test is more strict each of the 3 times you can run it. Code 10 means 1st cylinder, 20 means 2 so on and so forth.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Shuddering engine...UPDATE July,1

Reply #104 –
You can also try unplugging the O2's one at a time,  this puts the eec in default.  When only 1 is present, the eec will base the whole calculation off the remaining one.  I ran my ex's 92 Taurus this way for years.