[video] rough rpm, stall, and p0102

[kind153]

Hello all,

98 GT with 130k..vin K.
It one time stalled (had i have any idea it was a beginning) when I was taking left on 4-way stop. Right after making it through(D->N then start), it stalled again.

The RPM fluctuates (usually it goes down), and when it's bad enough + not enough throttle open, it'll stall.

I wasn't able to find any pattern as to when/how it happens..It is very intermittent.
Sometimes it'll do it when decelerating, accelerating, and even when idling. No codes as well.

That'd been going on for about 1.5 weeks, then check engine light came on today. I was glad. it was p0102 (MAF circuit low input).
So I tried to clean it, I guess it's clean..(?) but that doesn't solve the issue.
Unplugged the MAF sensor..same.

It had a recent A/C compressor replacement..if it's related in any way.

also, TRAC light comes on when it stalls while driving.. I'm not sure it's coming on (when it stalls) because car's rolling when engine's off..or car's starting ( when it's starting) when it's rolling. No ABS light is on. Tach is online.

I did my best searching for the answers..and here are possible candidates:
CPS
TPS
IACV
Bad ground for sensors
Bad PCM
Bad gas -- I think I can rule this one out because I've had more than 2 fillups and it still exists.
Bad plug/wire
Bad coil (pack?)
Vacuum leak
Fuel pump/filter
EGR?

Help!!

EDIT: Here's the video I caught when it was doing it: http://www.youtube.com/watch?v=Z5CbVHnMBBI

[matthew911]

I feel like I'm having almost the exact same problem. This morning it ran fine, but I noticed the TRAC (intermittently) and ABS lights were on. I got out of work, started it up, and it was stalling unless I kept my foot on the gas. I was very low on fuel so I managed to make it to a gas station, put some in, but it didn't help.

At this point it didn't want to start at all, even with the pedal to the floor. Turns over though. After an hour or so I tried again and it started up, but it ran rough while still having to give it some gas. Eventually it ran smoother and I was able to keep it running on lower and lower RPMs until finally it was running on its own, only to eventually stall again. Once again I can hardly keep it running. It doesn't appear to be drivable at the moment.

I'm not the most knowledgeable about cars so I'm not sure what the problem is here. Temperature gauge might have been slightly higher than normal, but it wasn't even halfway up the gauge. Only thing I've recently had done was recharge the AC with some R134a, which is similar to the original poster. Any ideas?

2000 GT, 149k miles

[01gpgt01]

P0102 DTC means MAF sensor low frequency. Id clean the maff.

[FordMan77]

He tried to clean it already. Either its not completely clean or the MAF may be toast.

Try unplugging the MAF and starting the car. It may need a bit of throttle to get started but then should run on its own. If it runs better then I'd say time for a new MAF.

[Scottydoggs]

check the wires that plug into the maf too, its a 98 and wires go bad, mine were all cracked and missing insulation.

[kind153]

Unplugged the MAF sensor..same.

Thanks for the replies.. guess I'm not a good writer; I did try driving without MAF, no changes.

[kind153]

I feel like I'm having almost the exact same problem. This morning it ran fine, but I noticed the TRAC (intermittently) and ABS lights were on. I got out of work, started it up, and it was stalling unless I kept my foot on the gas. I was very low on fuel so I managed to make it to a gas station, put some in, but it didn't help.

At this point it didn't want to start at all, even with the pedal to the floor. Turns over though. After an hour or so I tried again and it started up, but it ran rough while still having to give it some gas. Eventually it ran smoother and I was able to keep it running on lower and lower RPMs until finally it was running on its own, only to eventually stall again. Once again I can hardly keep it running. It doesn't appear to be drivable at the moment.

I'm not the most knowledgeable about cars so I'm not sure what the problem is here. Temperature gauge might have been slightly higher than normal, but it wasn't even halfway up the gauge. Only thing I've recently had done was recharge the AC with some R134a, which is similar to the original poster. Any ideas?

2000 GT, 149k miles

I heard when ABS and trac are on, (and tach is at 0 while engine running?) it may be the CPS..

[matthew911]

I heard when ABS and trac are on, (and tach is at 0 while engine running?) it may be the CPS..

Tach works. It seemed to only be able to go as high as about 4k RPM and wouldn't go higher. I pretty much had to keep it between 2k-4k RPM for it to keep running, except for the brief period where it ran on its own for whatever reason.

Also, when I started having the stalling problem, the ABS and TRAC were no longer on.

[shawngtp]

Its in limp mode and it sounds like you fuel resistor is bad and or your cps is too. My maf was bad and did the same thing. Get a new used maf or if you haz the money get a new one. Get back to us and let us know. There has to me a member in your hood that could help you out a lil more.

[matthew911]

Its in limp mode and it sounds like you fuel resistor is bad and or your cps is too. My maf was bad and did the same thing. Get a new used maf or if you haz the money get a new one. Get back to us and let us know. There has to me a member in your hood that could help you out a lil more.

Thanks. My dad and grandpa are both in the area right now, luckily for me. They're giving me a hand. There's a local junkyard that's always way cheaper than anyone else, so I'm guessing it's around $40 for a MAF sensor there. I'll find out tomorrow when they open. Other places want between $50-$65. I'm definitely too broke for a new one, unfortunately.

What sucks the most is it broke down where I work, which is 30 miles away from my house. Makes things more difficult.

[kind153]

Its in limp mode and it sounds like you fuel resistor is bad and or your cps is too. My maf was bad and did the same thing. Get a new used maf or if you haz the money get a new one. Get back to us and let us know. There has to me a member in your hood that could help you out a lil more.

So............can mine be the bad fuel resistor? how do I test it?

[kind153]

another question: I don't have "f/pmp spd cont relay"-- the slot's empty. am I supposed to one?

edit: I guess this is only for GTPs.. never mind!

[kind153]

anyone???

[RyanL]

seems like you need a new MAF! had almost the same problem, replace it! also if it isnt ur problem just tell the people the sensor you bought is faulty and try to return it! lol. but 99% sure its ur maf!

[kind153]

seems like you need a new MAF! had almost the same problem, replace it! also if it isnt ur problem just tell the people the sensor you bought is faulty and try to return it! lol. but 99% sure its ur maf!

really? but that happened when I UNplugged the maf as well.. that made me rule out the maf.

[BillBoost37]

Don't unplug it when the motor is running.

Unplug the maf and that reverts the pcm to run off a table instead of actual airflow. Expect that the fuel trims and other pcm learnable items need a bit to adjust.

Start the car and keep it idling if necessary. Once it'll hold itself up, go for a drive. After 10 minutes, does it seem any better?

Read this to understand how and why the maf works and what the code means is happening.
http://gearchatter.com/viewtopic1176...a916c525927703

BTW most problems are fixed in the "diagnostic aids" section of the FSM.

[kind153]

hmm..i think i did start and run without maf - but i'll try again.

[kind153]

After driving with maf unplugged, it stalled more often, rough-er idle, and less mpg.
(??) so I plugged maf back in today, and it's been better. I'm confused..