95 Taurus Multiple problems

[psycho_njm]

my wifes taurus GL..... first off i hate the car, but she loves it and i am forced to work on it.

anybody got any idea why the tranny would shift super hard from 1st to 2nd and smooth the rest of the way to 55? i first checked the computer and got O2 and EGR codes. yep, i replaced them all, 2 O2 sensors, 1 EGR valve and the 2 sensors to the left of the EGR. i had the computer cleared of all codes and the car drives fine for roughly 5 miles then starts acting up again. computer again gives egr and o2 codes though brand new. any ideas?

problem 2: just yesterday the car will not drive down the road.... the car will start and run but when the accelerator is pressed the car wants to die out like not getting enough air or not enough gas. the car also back-fires out of the upper intake when accelerator is pressed. just tonite i replaced the throttle position sensor, no change. am i giving money to a lost cause or can this be fixed? Thanx for your time

[lectraplayer]

I hate when this stuff happens! I bet the air and fuel filters are clean, but do check them. If it works for a little while and then starts forking up, I would suspect the "computer" that manages everything. This one's hard to prove short of replacing that box and seeing if the trouble goes away.

What model year is it? Never mind, '95. I bet the computer's strapped to the side of the battery, if it's like my '96. It backfiring through the air intake is usualy from the timing being way early. Timing's controlled by the computer. Could it be telling on itself?

[psycho_njm]

oh yeah the most important info... its a 95 with a 3.0 EFI

[psycho_njm]

well i guess another trip to the local scrap yard to look for another computer is in order, cuz i sure as hell am not buy a new one. thanks buddy

[lectraplayer]

Originally Posted by psycho_njm

well i guess another trip to the local scrap yard to look for another computer is in order, cuz i sure as hell am not buy a new one. thanks buddy

Hold on! I bought a repair manual for my Taurus today in relation to my problem, and I'm seeing in there about marking the crankshaft pully @ #1 top dead-center. Maybe if you can turn that pully a little bit "off", then maybe you can adjust the timing to get it back within a good tolerance. Something to play with before you bring home another computer and end up with the same result. I thought the computer set the timing to anywhere within 360 degrees, but it may be only 45 degree or so. If you can mechanically advance the timing to where the best spot appears to be within mechanical limits (by turning the pulley on the crankshaft), then the computer may can do the rest as you drive the car.

Remember that the spiky rear part of the pully is what the computer uses to know where the engine's at. It must be turned to reflect your changes, but I assume it's part of the pulley itself.

I do recommend buying a repair manual from Autozone (or wherever). It shouldn't be too expensive and would pay off big.

[psycho_njm]

Well, after i put another fuel filter on it today and got gas in my eye ( i cussed alot ), things seemed to get better. still a back fire once in a while when starting. i think i have a bad Mass airflow sensor, it just seems like the most expensive repair for some stupid little problem. im gonna look into that alittle more. as for the timing... i just spent a week trying to time my ranger (92) with the same motor, finally got that right and it screems with all unholy tire burning badness! the ranger has alot more miles on it and it was just a hair off dead nutz. with that in mind, i would assume that the ol' lady's car, with alot less miles, would even be off. im thinkin its the mass airflow sensor. i should know more in a couple days, work permitting, whether or not that will hold true. if so, great! if not, im sell the hateful hunk o' sh!t. Thanks for your input, i really appreciate it.

[lectraplayer]

That backfiring has me thinking timing. A bad airflow sensor isn't likely to contribute to this backfiring, but with today's cars, you never know. I'd think it just plain wouldn't run worth a crap with a bad airflow sensor as it would still be "hitting" when it is supposed to, just with a crappy fuel ratio.

Also, the tranny downshifting, how does the transmission fluid look? Does it have enough? Is it red or black? etc. If it's bad low, that problem will likely go away when more fluid is added (so my repair manual indicates).

[psycho_njm]

right right.... but the running crapy has me the most concerned with the air flow sensor. because its just backfiring now, not when it was running ok. im thinkin that im possible getting to much fuel to air and causing a backfire.... am i thinking the right direction here? im not tryin to discredit your opinion, just that it seems more unlikely to be timing because it just started backfiring. to me it just acts like is choked for air. but no progress made today, worked late again, just waiting for an opportunity to get to the other office and swing by the scrap yard for parts.

[lectraplayer]

Originally Posted by psycho_njm

right right.... but the running crapy has me the most concerned with the air flow sensor. because its just backfiring now, not when it was running ok. im thinkin that im possible getting to much fuel to air and causing a backfire.... am i thinking the right direction here? im not tryin to discredit your opinion, just that it seems more unlikely to be timing because it just started backfiring. to me it just acts like is choked for air. but no progress made today, worked late again, just waiting for an opportunity to get to the other office and swing by the scrap yard for parts.

I see your thinking, but I'm still convinced that if it just isn't getting air, it would only run crappy, but would still be lighting the gas at the right time, and thus not backfiring through the intake. If it's lighting the fuel way early (timing way early), then it will run crappy here as all the fuel's energy isn't being properly directed, or is being blown back up through the intake (the backfire). If you're not getting the fuel's energy into the engine by lighting the fuel precicely when the piston hits top dead center, or a couple degrees afterwards, then the engine will not run like it should, be it a slight and unnoticeable reduction of power for lighting a few degrees early, or, as demonstrated here, simply not running worth a cuss and backfiring through the intake since the fuel's being lit while the intake valve's still open and almost no energy from the fuel's being transferred to the crankshaft.

If you can get the timing fairly close, the computer will likely make the final adjustments to get the timing dead on.

[psycho_njm]

yeah you're right about the timing.....

as for the tranny... its just shifting hard from 1st to 2nd. thats it. what makes the thing worse is it only does it sometimes. i've done the filter & fluid change to try and fix the problem and to no avail, it still does it. the fluid looked really good when i changed it too. so i would assume it had been done prior to my purchase of the car. im wondering, being that it has an electronically controlled transmision (so im told) and controlled by the computer. if the computer tells the engine to run harder to compensate for some error, then wouldn't it also make the tranny work harder?

[lectraplayer]

Originally Posted by psycho_njm

yeah you're right about the timing.....

as for the tranny... its just shifting hard from 1st to 2nd. thats it. what makes the thing worse is it only does it sometimes. i've done the filter & fluid change to try and fix the problem and to no avail, it still does it. the fluid looked really good when i changed it too. so i would assume it had been done prior to my purchase of the car. im wondering, being that it has an electronically controlled transmision (so im told) and controlled by the computer. if the computer tells the engine to run harder to compensate for some error, then wouldn't it also make the tranny work harder?

It may be a computer-related thing. ...of course, knowing today's cars, if you correct the timing issue, maybe the shifting issue will also be resolved. When it does run decently, it may still be running harder to regain lost power from the timing being early, which may affect the transmission. Also, can you duplicate and isolate the conditions that makes it jar your teeth out? Mine seems to do it, especially, when I go WOT to pass somebody, let off milliseconds before it downshifts (maybe because I am unsure of the clearances I'm seeing), and then return to WOT within a second of letting off. I guess this kinda confuses the computer on what I'm trying to do when I let off, and it's too ready when I get back on it. It needs to first let everything load up for about 20 more milliseconds and then shift.

[shorod]

Originally Posted by lectraplayer

It may be a computer-related thing. ...of course, knowing today's cars, if you correct the timing issue, maybe the shifting issue will also be resolved.

There certainly could be a lot of truth to this. I'm not sure if the "regular" Taurus tranny/PCM is programmed like my Taurus SHO, but on the SHO the engine timing is retarded during shifts to reduce the power during the shift and hopefully extend the transmission life, as well as make for a smoother shift.

-Rod

[lectraplayer]

Originally Posted by shorod

There certainly could be a lot of truth to this. I'm not sure if the "regular" Taurus tranny/PCM is programmed like my Taurus SHO, but on the SHO the engine timing is retarded during shifts to reduce the power during the shift and hopefully extend the transmission life, as well as make for a smoother shift.

-Rod

On my GL, I can feel a greater surge of power right when it shifts. I guess it's mostly inertial engine momentum, or as you're saying, it retards the timing and my timing's a little early.

[psycho_njm]

Everything is all better!!!! All computer codes are gone, car shifts fine, and no more on/off "check engine" light!!! ok, now some model taurus's have map sensors and some have mass airflow sensors, the part the auto place will sell you is the same thing in both cases... It's the Mass Airflow Sensor. the Aluminum "can" attached to the air filter box. the actual "MAP" sensor is the black or grey plastic thing attached to it with center posted security screws. after i give $85 for a new one... i got a whole new car, so to speak, i hope this helps someone else. Thanks for the ideas and the support guys!!!

Nick

[shorod]

Originally Posted by psycho_njm

Everything is all better!!!! All computer codes are gone, car shifts fine, and no more on/off "check engine" light!!! ok, now some model taurus's have map sensors and some have mass airflow sensors, the part the auto place will sell you is the same thing in both cases... It's the Mass Airflow Sensor. the Aluminum "can" attached to the air filter box. the actual "MAP" sensor is the black or grey plastic thing attached to it with center posted security screws. after i give $85 for a new one... i got a whole new car, so to speak, i hope this helps someone else. Thanks for the ideas and the support guys!!!

Nick

A MAP sensor is a Manifold Absolute Pressure sensor. It connects to manifold vacuum and contains a pressure switch inside. The Mass Air Flow sensor uses a heated wire and a reference wire and monitors the amount of current required to keep the heated wire at a set temperature. The two sensors are not the same and are not interchangeable. If the parts store told you they are the same, they are in error.

-Rod