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View Full Version : 95 5-speed running like crap...



91BLOWNSC
08-12-2004, 04:40 PM
Alright heres the scoop guys, the car idles perfectly at a stop without a miss or anything. But when I go for a take off (just normal or hard) the tach falls slightly like it is going to stall. The car hesitates and then comes back to life.

Another example, if I tap on the gas consecutivley and say keep it around 1500 rpm. making sure im taping the gas like blipping the throttle, it will pick up like normal sometimes, and other times the tach falls back down to about 1200-1300 like someone stopped the airflow on the engine.

Also while I am driving and apply the gas it also hesistates but once it starts moving it seems to be ok. A guy at the local ford shop ran a diagonostic on it and said that the computer wasn't "reading the MAF sensor" and I have tried running the car with and w/o the MAF sensor plugged in and it also runs like crap with it unplugged. So my question is, do you think it is an accurate diagonsis of the problem and should I replace the MAF sensor itself? Because it does run differently when its plugged in so I woulda thought it would be reading it. It is a C & L Maf sensor with a yellow sampling tube i beleive to be right with my 36 lb injectors. I just dont' know what else to make of it. My next question is if I FIND out that this is my problem the sensor has to be out of a late model SC correct? What are other possibilities that it could be?


The HG's were just done on the car and the car was sealed back up perfectly. It did it before the HG's and it is also doing it after.

blue94sc
08-13-2004, 12:07 AM
Hey 91BLOWNSC.
It sounds like the MAF sensor is bad. You could check the EEC youself to see if it is listing a MAF code with a hand held scanner. Or use a voltmeter on the diagnostic plug to read the pulses generated by the EEC. Auto Zone I believe will scan your car for free if you want a second opinion. Looking at the code chart, if the MAF sensor is bad then you should get one or more of the following codes;
26 - MAF Sensor out of range
56 - MAF Sensor out of range (high)
66 - MAF sensor circuit out of range (low)
or (most likely)
157 - MAF sensor below minimum voltage
158 - MAF sensor above maximum voltage
159 - MAF sensor out of range

Another possibility is the throttle position sensor. I have had trouble with my 86 N/A 3.8 Mustang stumbling through accelleration. I had to bench test the TPS and found a dead spot in the cruising speed position.
The codes will help point in the direction of the problem.
Hope this helps!

91BLOWNSC
08-13-2004, 01:02 AM
Hey 91BLOWNSC.
It sounds like the MAF sensor is bad. You could check the EEC youself to see if it is listing a MAF code with a hand held scanner. Or use a voltmeter on the diagnostic plug to read the pulses generated by the EEC. Auto Zone I believe will scan your car for free if you want a second opinion. Looking at the code chart, if the MAF sensor is bad then you should get one or more of the following codes;
26 - MAF Sensor out of range
56 - MAF Sensor out of range (high)
66 - MAF sensor circuit out of range (low)
or (most likely)
157 - MAF sensor below minimum voltage
158 - MAF sensor above maximum voltage
159 - MAF sensor out of range

Another possibility is the throttle position sensor. I have had trouble with my 86 N/A 3.8 Mustang stumbling through accelleration. I had to bench test the TPS and found a dead spot in the cruising speed position.
The codes will help point in the direction of the problem.
Hope this helps!



Thanks! I will definitely go have them test it tomorrow or saturday for that matter. Something I forgot to add is the car will stall while I am at idle for a bit. It just starts stuttering and then dies. I may just go to my local murays and scan it myself. But sometimes I don't think Im using it right. Thanks for the codes tho I will write those down.

I see your located in toledo, im down there often actually. We should meet up sometime! Your ever take your car to milan?

hytorksc
08-13-2004, 08:49 AM
i would say clean your maf wires (the delicate wires inside the sampling tube), and replace your cam sensor. my 5spd behaved very similar to this, and all i did was change the cam sensor, and it now runs perfect. also give some attention to the ignition switch inside the steering column- it seems that high mileage SC's tend to have this problem (happened on both my SC's), the inside of the switch box (upper contacts) was not making full continuity with the bottom contacts- this was causing all sorts of electrical problems with ignition, and brakes.

blue94sc
08-13-2004, 12:41 PM
Thanks! I will definitely go have them test it tomorrow or saturday for that matter. Something I forgot to add is the car will stall while I am at idle for a bit. It just starts stuttering and then dies. I may just go to my local murays and scan it myself. But sometimes I don't think Im using it right. Thanks for the codes tho I will write those down.

I see your located in toledo, im down there often actually. We should meet up sometime! Your ever take your car to milan?
I just bought my 94 this year in late June. I have had to do a little work on her; brakes, front strut bushings, etc..
She's still stock as of now. I hope to get the exhaust done as soon as I sell my 86 Mustang hooptie. Then it will be the intake mods next.
I haven't raced her yet. She has 140K miles and the trans shifts hard in 2nd (probably synchros). I plan or replacing the original clutch and rebuild the trans while it's apart.
Racing would be a real pain with a sticky 2nd gear.
I hope to make it to an event sometime soon.
LMK if your going to be in Toileto (ha). I'm right off of 75 and Alexis Rd.
Later.
Bill

91BLOWNSC
08-15-2004, 06:03 PM
Well the codes were 126 BAP sensor out of range, code 157 MAF sensor voltage to low and code 181 and 189 to say that both banks were running lean.


My next question is, are all the bap sensors from 89-95 the same for our SC"s and interchangable? And where exactly should I get a new MAF sensor...pull it off an SC at the J-yard? And are those interchangable?


Thanks.

Charkly
08-15-2004, 10:22 PM
you need a maf for a 94-95 sc as the injectors are larger and the transfer function of the maf is different. the bap sensor i believe is interchangable. i have both for a 94 sc that i can lend you to test before you buy new, or if youre sure thats your problem ill let then go for a low price. good luck, mike

91BLOWNSC
08-16-2004, 04:38 PM
Charkly, that would be awesome. Though, if we could make arrangments on what you think you might like for them if they do work it would be great. I am going to school and on a limited budget, I had a few other things drain me recently so I dont' want to get them all the way over here and not have the money for them. We can talk through e-mail if you'd like. [email protected] is my e-mail. Thank you for offering also!! :)

ThunderDave
08-16-2004, 05:45 PM
Hey blown,

I think the maf being bad might cause the lean running codes you got. If the maf isn't operating right, it will affect the air/fuel mix and cause a lean or rich condition. Get the maf replaced and should clear up the lean condition. I'd check the codes again though, just to make sure.


David

TwoToneThunder
08-17-2004, 02:25 AM
hey 91blownsc i live in southeast mich to what city do you live in? i hope to make it to milan sometime soon

91BLOWNSC
08-17-2004, 03:49 PM
I live in the monroe area. you?

91BLOWNSC
09-15-2004, 12:37 AM
Alright guys, Well I tried cleaning my MAF sensor and that didn't work. I have been taking it out every once in a while, including just tonight. It seems to run horrible when I first start it up and always wants to stall. Which wouldn't make sense because is it even usign the MAF sensor at this point in time? Well anyways after it warms up a bit she seems to be ok and idles like a dream. But you give it gas and its almost like the car doesn't want to rev kind hesistates and what not.

Another sign i seem to have is everytime I go into boost mode the check engine light will come on. Or if I get on it hard. So i pulled it back into the garage and let it idle with the MAF plugged in and it ran like crap and started to stall (which it does if you let it sit to long) and before that happened i unplugged the MAF and the engine ran smooth as silk. Plugged it back in and the engine bogs down again and wants to die.

Like I and everyone else thought it was the MAF because Like i said when I ran the codes it came up the MAF sensor voltage was to low and the BAP sensor was bad. So I put new ones on the car and it ran the EXACT same way, can someone please explain what they think the problem could be. I am out of ideas. Thanks.

91BLOWNSC
09-15-2004, 07:24 PM
Come on, anyone?

ThunderDave
09-16-2004, 06:32 AM
Come on, anyone?


It still sounds like it might be the maf to me. If it will run without it plugged in even if it's bad and just die with it plugged in, I would think you need a new one or maybe there is something in the wiring harness. Doug Franklin had a problem like that and it ended up being the maf that was bad. Check with him and see if he can tell you anymore about it.

Good luck!

David

91BLOWNSC
09-16-2004, 03:30 PM
But I tried one that worked off of another SC. And it ran the same way! Thats whats pi$$ing me off. I am not sure what else to try.

ThunderDave
09-16-2004, 06:18 PM
Did you do a fuel pressure test? I know that doesn't have anything to do with the maf or bap. Mine was running like crap and I went through all the tests and checked everything and found no faults. Turned out one of my cats was clogged. Punched them out and runs good now, although I do still have a high idle issue I'm working on.

Just a thought.

David

91BLOWNSC
09-16-2004, 11:55 PM
No haven't did a fuel test yet. But that is something I planned on trying next. There are no cats on the car as they were removed by the previous owner. So I know that can't be it. I will try that fuel test and let you know. What should the pressure be at?

ThunderDave
09-17-2004, 05:39 AM
With just key on, mine was at 40. I think 34-40 is acceptable range with it running. If you pull the vacuum line off the regulator, I think it should be 38-42. The pressure should go up with throttle as well to about 50 at WOT. If one of those isn't right, you might have a fuel problem. Also, the system should be able to keep the running pressure for at least 15 minutes after shutting the car off.

David

91BLOWNSC
09-26-2004, 01:00 PM
Well I did the fuel pressure test and the pressure was at a constant 31 PSI with the regulator vaccum line still hooked up. And then I got on her a little bit and she jumped up to about 47 PSI. Not quiet sure what all that means, but it seems halfway normal to me and the car still runs like crap. I dont' know what else to do.


I thought about cleaning my 02's for the heck of it with a torch. I heard this mentioned on the board many times before. How long exactly are you supposed to hold a flame to them?

ThunderDave
09-26-2004, 02:44 PM
Well I did the fuel pressure test and the pressure was at a constant 31 PSI with the regulator vaccum line still hooked up. And then I got on her a little bit and she jumped up to about 47 PSI. Not quiet sure what all that means, but it seems halfway normal to me and the car still runs like crap. I dont' know what else to do.


I thought about cleaning my 02's for the heck of it with a torch. I heard this mentioned on the board many times before. How long exactly are you supposed to hold a flame to them?


I'm not sure about the torch thing. I've heard of that being done, but also heard too much heat on them isn't a good thing either. The 31 pounds sounds low to me. Try it with the vacuum line off and see what kind of pressure you get. With the pressure that low, it could be the pump or regulator. The 47 sounds a little low as well. I think it should go up to at least 50 pounds when you go WOT.


David

95SC
09-27-2004, 03:40 AM
But I tried one that worked off of another SC. And it ran the same way! Thats whats pi$$ing me off. I am not sure what else to try.


Hey man... I had a problem alot like yours with my 95 5 speed, it would idle great and then when I tried to take off it would stutter and hesitate, and then all of a sudden it would take off like mad!! I did the same Mass air Flow tests that you did, and The only thing that fixed my problem was that I took it to ford, and had them replace my Computer... After that my car ran perfect again...

Hope this helps,

David.

Jimmy 2Coupes
09-27-2004, 07:50 PM
91BLOWNSC, if you want to drive over to Adrian sometime I could take a look at it for you. My bet is that it's something simple. I have plenty of tools and a lot of good spare parts as well as a scanner, fuel pressure gauge, propane, ect. We could even put my EEC in in your car to see if it makes a difference.