94 need advice

[RogerStout]

OK I am going to try to explain this the best I can. I am new to mustangs and V8's in general. I purchased my car with existing issues. It ran like crap and seemed to be out of time.

So I replaced the wires, cap button, plugs, pulled the dizzy and reinstalled at TDC and set the timing and adjusted the fuel pressure.. was at 50psi now 39psi at idle. Now just assume I am not a total idiot and did all that right.. :) Possible I screwed something up..

The car still runs like crap, Idles rough and I punch it it falls on its face, sputter badly. What else can cause this behavior? About 5 things come to mind but I dont want to just start throwing parts at it..

Looking for some ideas any advice would be appreciated. Bad Dizzy? Vac leak? bad ECU?

[Killercanary]

Did you check to see that the mass air sensor matches the injector size? If it does try cleaning the MAF wires with a q tip and either alcohol or carb cleaner but be gentile.

[RogerStout]

I will check it out.. thanks. I have cleaned the maf.

[cwh19]

Did you change the fuel filter and run some injector cleaner?

[Martin0660]

Have you actually pulled codes on it? If it wont give codes that could point to a bad ECU ...

Do you know if anything was done to the car mod wise (cam, etc)? I know those 94/95 cars sometimes freak out about some changes. Paul and Troy know more here than I do ...

Have you done a simple compression test on it to start? Had a vacuum gauge on it?

[White5.0]

x2 to everyone that posted before me..it is all great advice. adding to that i would say check all grounds and make sure fuel pump is working properly

[yeahloh95]

if you have cleaned the maf, my next thought would be 02 sensors and i agree with bob check for codes, is the check engine light on ?

[no1sirbutler]

Roger forgot to add the fact that after he set the timing to 12 degrees total advanced, the car idled nice and smooth and would climb the rpm's normal.....2 days later he comes out w/ not touching anything and its running like crap again. He checked the timing and its back to 9 degrees. Adjusted back to 12 and runs worse, I have never seen anything like that so I told him to post up here for advice.

We did have a massive downpour Mon nite so I was thinking maybe something got moisture in it. Also wondered if it was possible for the gear on the dizzy to come loose and spin causing the timing issue?

[RogerStout]

^ What he said.. At this point I am thinking that is Human error like I didn't get the dizzy tight or something.. IDK but two days ago I had it idling and revving nicely could not drive it cause the interior was out (its back in now)

When I first got the car I was getting an intermittent CEL it would randomly come on and shut off in the way home, it was running so rich it was making me ill smelling it. As of my changes no CEL now the battery light poped up yesterday out of the blue.

The car has a few mods.. gt40p motor, 70mm bbk tb, mac shorty, cobra up and lower intake, injectors are cream in color so not sure what # that is. 1.72 rr, Cam? not sure. Fuel pump is not stock you can hear it running over the car idling and its dumped.. BBK cold air intake under drive pully.

I have not checked to see if its the stock MAF or the MAF that is stock with the gt40p. Other than timing and fuel pressure I have not messed with it so there are tons or possibilities I suppose. From the motor swap IDK if the car has ever run right. The tires are bald so it must have been running good at one time.

I am going to purchase a code reader looks like I am going to need it. I have had a few people tell me o2 but as I understand it the car only uses the o2 in closed loop, at WOT it switches to open loop, this is correct? If so o2 would not explain why it falling on its face at WOT.

here are a few photos..




Injectors


before I got the dizzy back in.



I dont know anyone that has a sn95 other than me so I cant parts swap I am forced to buy parts and see if it fixes it. That can add up quick...

I must assume that the car has never been tuned..

I dont know the cars history I purchased it from a kid in Summerville (didn't know anything about the car) and he purchased it about a year prior from a guy in NY.

[speedracer]

Did the gear on the distributor have a hole with a roll pin in it to hold it in place?

[RogerStout]

Did the gear on the distributor have a hole with a roll pin in it to hold it in place?

Yes sir I believe I did see that..

[Mark Aubele]

Are there any modifications beyond the intake manifold and rockers? Cannot tell if they are stock heads, and has it had a cam swap?

[RogerStout]

has gt40p heads, Cam I dont know no easy way for me to tell..

[yeahloh95]

Could the balancer have turned? They are known for going bad

[RogerStout]

That should be easy enough to check. I will put the motor back on TDC by my dizzy marks and see if the pointer is still correct. I dont think its a stock balancer as is has a full scale and numbers on it. I dont think the stock unit had any numbers.

[somethingclever]

bouncing timing could be worn dizzy/bad pickup

[White5.0]

I dont what size those injectors are...i know on a fox body they are orange stock. So, if you have say 24lb injectors but the stock mass air meter that is used for 19lb injectors it'll run poorly.


also the pointer on the distributor has to be pointing to the #1 cylinder when that cylinder is at TDC on the Compression Stroke...NOT just TDC on any stroke. so i would check that to make sure.


the o2 sensors have nothing to do with WOT so if its running poorly at WOT you can throw out the O2 sensors as being a problem ( at least i think so...I dont know as much about 94/95 computers and how they differ from the fox bodies)

[cwh19]

When I first got the car I was getting an intermittent CEL it would randomly come on and shut off in the way home.

Thats typical check engine light procedure for vacuum issues and 02 sensors; from my experiences anyway. Id get a code scanner and check them. They are only like 50 bucks for obd1 cars.

[RogerStout]

Maf is f2vf-12b579-a1a 70mm from what I am reading a crow vic or newer mustang.

Injectors are XS2E-A5B stock for the motor (came out of a 1997-99 explorer) dont know the exact year.

Just to update...

I am going tomorrow to get a code reader.

I pulled the vac line from the regulator and it smelled like fuel.. I know leaking is bad but smelling like fuel is sign of a failing regulator?

[yeahloh95]

Yes it should not have fuel in the vac line