Car is STILL a slug...

[ratio411]

I am not bagging on SN95s, don't get me wrong.
My son's 94 GT vert has just been a gutless slug since we got it, and nothing seems to help. The fact is I KNOW it should run better than it does. Whatever is wrong is probably one of those stupid little things that make you go "DOH!" when you figure it out. I am just tired of trying to figure it out.

I am posting as a rant, sure, but welcome any comments.

I'll post details in the next entry.

 

[ratio411]

We spent all day yesterday tuning it AGAIN, and doing some light modding.
1994 GT vert with AOD and 2.73 gears
Hollow cats, stock headers, MAC flowpath cat-back.
Cold air intake... type with cone filter and aluminum tubing.

Tune:
Plugs gapped at .050" (new Autolite copper)
New cap and rotor
Timing set at 14* (have tried 5* to 20* in past)
New TPS
Clean IAS
Clean EGR
Clean TB
Clean MAF
New ECT sensor
Check throttle blade for 'full open' with pedal
Rebuilt injectors, all working strong with bench test
35 psi fuel pressure at idle, 42 psi with vacuum removed
All cylinders within 10% on both wet and dry compression test
Cleaned air filter
Check ALL visible connections
New PCV

Mods:
Removed GT intake and replaced with factory 94 Cobra (GT40) upper and lower.
Replaced all plastic vacuum lines with new rubber
All rubber vacuum lines replace with new rubber

The result is the car runs better than normal now.
However, it is still unusually slow compared to even my 5000# 5.0 EFI 1990 F150, or my son's Fox body Fairmont with 5.0/AOD/2.73 gears. Our other 5.0s have more power, more torque, snappy throttle response, good idles, good accelleration, good sound. The 94 has NONE of these attributes.
I know it shouldn't be a 'rocket', but it should be better than what it is.

It has soft response, often feels like it holds back when you push the throttle, or sometimes even surges. Sometimes, not everytime, it takes a gulp of air and goes flat when you gas it, then it catches and picks up RPM. Revs are very slow and lazy. Even when it runs perfect, it feels lazy and weak.
The idle goes from silky smooth at times, low and searching, then to a high that doesn't want to settle out. Although, with the intake change, high idling is now less common, so there must have been a small vacuum leak. Now it is more likely to idle lower and lower, then surge up for a second before declining lower and lower again.

Some notes/concerns:
I just don't have any more dough to throw at getting an IAC right now.
I realize that could be one issue, especially with idling, but shouldn't be with the power and throttle response, so in it stays.

I know the gears hurt seat of the pants power, but my son's Fox has the same gears and hauls butt for what it is anyway.

I didn't put the Cobra intake on looking for any power gain. I just got it for future growth and since we were rebuilding the injectors, cleaning the engine, and looking for vacuum leaks, I figured we'd throw it on.

Where is the Baro Sensor on the 94???
I failed to notice that I didn't see the sensor...
Then I jolted awake last night and couldn't sleep good again when I realized I never saw a baro sensor on the car, and on other Fords, the sensor is 'in your face'.
This sensor 'should' have a lot to do with throttle response, as much or more than the TPS, and I totally forgot about it because I couldn't see it.

Can the O2 sensors cause any of this weakness?
They 'looked' good, and are expensive, so they didn't get replaced.
They were replaced about 18 months ago, and the car doesn't get alot of miles.

Fuel filter was replaced about 2 months ago.

Car doesn't smoke anything at anytime.
However, at idle I noticed a potent exhaust odor, beyond normal.
Don't know if it is running rich on the road though. Could just be rich at idle???

Thanks for reading my huge post if you made it this far!
Dave

 

[BIGDATOWN]

That seems like alot of gap on the plugs. Try .45 and put the timing on 10 degrees exactly!

 

[ratio411]

That seems like alot of gap on the plugs. Try .45 and put the timing on 10 degrees exactly!

I'll give it a try.

 

[ratio411]

I do have my doubts though.
I run .050" gap on all our 5.0s, and 14-16 timing.

Is there a reason those numbers won't work right on an SN 95 vs a Fox or an F150?

Just curious as to the reasoning.

 

[revhead347]

14 degrees of timing does seem to work a lot better. .050" is stock gap, but it seems to work better at the .040" gap range.

Kurt

 

[Stangstroke]

I am not bagging on SN95s, don't get me wrong.
My son's 94 GT vert has just been a gutless slug since we got it, and nothing seems to help. The fact is I KNOW it should run better than it does. Whatever is wrong is probably one of those stupid little things that make you go "DOH!" when you figure it out. I am just tired of trying to figure it out.

I am posting as a rant, sure, but welcome any comments.

I'll post details in the next entry.

Man i feel your pain but 94 and 95's are total slugs especially with an automatic tranny and that gear ratio i had all those things going against me as well. If you want to wake it up a bit drop the 2:73 gears and put in a set of 3:73 that'll wake it up about as much as you can for one of those cars. The next thing you can do is keep your eyes open for a cheap T5 and drop that boat anchor of a tranny that thing sucks all the fun out of the car. Just my 2 cents!!!

 

[jdl95stang]

I think I would replace the ignition coil. We had a fox body that tried to blow out the spark, especially under a lot of throttle

 

[jdl95stang]

happens more than you would think

 

[TonyS]

Have you checked your cam timing? If your cam has jumped one tooth, you'll experience all the above. Worth a shot.

 

[jdl95stang]

Agreed

 

[BlownFiveLiter]

Have you checked your cam timing? If your cam has jumped one tooth, you'll experience all the above. Worth a shot.

The likelihood of the timing chain jumping a tooth is about as likely as I am to walk outside right now and get hit on the head by a satellite falling back to earth. If the chain's going to jump, it's going to break first. Now if you mean the distributor gear, well that's still not possible. You just rotate the distributor more until the timing is set. It doesn't know, or care where you align the teeth. As long as the harness has enough play, you can rotate it as far as you want until the timing is set. The most likely reason is that it's got an AODE and 2.73 gears. It's a dog from the factory, and minor bolt-ons aren't going to make it into a race car. Stock everything, except a Cobra intake means you probably went from running consistent 15.5xx, to running 15.2xx. Sad? Yes, but true.

 

[jdl95stang]

True, it is unlikely, but I wouldnt say impossible

 

[jdl95stang]

Have you replaced the plug wires? If so, I still say I would go for a new coil.

 

[final5-0]

In the past, when the cam gears were plastic you'd see the chain
break off a few teeth and jump time

Also ... when the chain got LOTS of miles you might see it

anyway ..........

Honestly ... You got ALL the things that hurt going against you

Vert=heavy
Auto Trans=power sapper
Tall ... Very Tall... gearset with 273's=no torque multiplication

The tall gears working with the AODE is a real killer
These two alone make it so hard to overcome sitting still

IMHO ... mods like intake, headers, and other motor mods which
will for sure make more power is just not where its at for your app

You gotta over come the main stuff that holds you back when you wanna
move quickly :Word:

You just can't multiply torque quickly with those 3 things

Gear it up first with some steep gears
then
A higher stall tc would really wake it up

Grady

 

[BIGDATOWN]

My 95 car hates anymore timing than 10 degrees, On 10 degrees it will blow the tires off in first, at 14 it doesn't even chirp them! Oh and just throwing it out there because I forgot this weekend but you are pulling the grey pill before setting the timing correct?

 

[jdl95stang]

If the engine is running propperly, yes I would have to greatly agee with grady. I am under the impression that you are having engine issues also. When you say that it "takes a gulp of air and goes flat when you gas it, then it catches and picks up rpms", that doesnt sound like you are saying that it simply lacks power. Just trying to get things streight with what is going on

 

[Stangstroke]

The likelihood of the timing chain jumping a tooth is about as likely as I am to walk outside right now and get hit on the head by a satellite falling back to earth. If the chain's going to jump, it's going to break first. Now if you mean the distributor gear, well that's still not possible. You just rotate the distributor more until the timing is set. It doesn't know, or care where you align the teeth. As long as the harness has enough play, you can rotate it as far as you want until the timing is set. The most likely reason is that it's got an AODE and 2.73 gears. It's a dog from the factory, and minor bolt-ons aren't going to make it into a race car. Stock everything, except a Cobra intake means you probably went from running consistent 15.5xx, to running 15.2xx. Sad? Yes, but true.

See listen to us get rid of the 2:73 gears and put in 3:73 it's a good all round gear

Then ditch that tranny sucks the fun out of your car

If you don't do those things first your throwing your money away for nothing and you'll still have a dog on your hands

 

[toyman]

A couple of thoughts. My '94 GT 'vert came with the 3:27 gear option. However, the first thing I did was to swap out the gears for 4:10's, install a shift kit (Transgo HD2), added a tranny cooler and a built TC. Not the fastest car by any means but you could sure roast the tires in first gear. The AODE's are very capable with the correct mods built into them.

The second thought relates to timing. The OEM balancers are prone to failure and will slip on the inner hub. If that has occurred and the timing has been reset the actual timing will be a way off. If you can see any rubber protruding from the hub or a visible wobble the balancer is toast. You shouldn't have an issue with the plugs gaped at .050". Spec is .054". Also, stay with 87 octane gas.

 

[ratio411]

Thanks for all the ideas.

The problem is a 'problem' though.

I know the car won't be fast with those specs, however, it should run smooth and be able to pull itself without being lazy.

When you hit the pedal, it sometimes stalls or gulps air followed by silence, while you are still on the pedal, then it goes. Sometimes it pops in the intake when you goose it. It lopes like it has a cam...

Now that we apparently have all the vacuum leaks out of it, it idles low and has died putting it in gear.
(New symtom since we did the work this weekend. Before it idled higher most often.)

It runs better, but still shouldn't lope like it has a big cam.

The balancer has gone out before, this doesn't give those symptoms.

The plug wires are relatively new and 'look' good, so they were not replaced.
I ran my hands down each wire while running and I never got 'bit' by the spark.
Old plugs looked PERFECT when they came out.
No signs of ANYTHING being off. They were, if anything SLIGHTLY slanted to running lean.
(VERY SLIGHTEST white color, but mostly perfect gray and spotless clean)

I might buy into the coil being weak... ??? I have never had one go out that way before though.
Usually they either work or don't, and will often run fine cold, but cut out when warm/hot.
???? I might try a spare coil.

No one addressed where the Baro sensor is on these cars?
That sensor feels when you open the throttle quickly and is important to throttle response.
I assume our cars have them like every other 5.0 EFI ever made?