Occasional Hesitation

[greeffs]

thanks for the response stevo2
answers : car was fine before timing belt replacement
97 000miles
NO , consistent hesitation
2000 2.0 4 cylinder auto
no engine codes on hand held scanner
have replaced plugs , wires ,filters ,oil and checked the VCT solenoid is OK. no vacuum leaks
yesterday scanned the car with a snap-on unit and it shows timing is good but less than perfect MAF sensor readings Coincidence maybe.?

[will76]

I have a 2000 Mystique, 95,000 miles, that just started this week giving me the same issue. When I am on the highway it pulls, jerks, feels like it is running out of gas, shifting hard, and the rpms are going crazy. I've noticed twice that the overdrive light has flashed while driving, but eventually turns off. When off the highway going slower, it will do it to a lesser degree and is not as nerve racking, but still occurs. I dont know where this problem will take me and if it will be the same as the other replies.

I have read the stories of people with this issue that have had cars stall, need a certain amount of gas to get up hills or accelerate, but this has not happened yet, again as it has only been occurring for about 5 days now. I just brought it into Autozone for them to check the codes, but nothing came up as with other replies. The Check Engine has not come on at all. A Ford dealership will charge $130 for a full diagnostic test and guarantee they will find the answer and that it will will be under their 12 month/12,000 mile warrenty. However, I believe they will find that it needs a new engine or transmission, which most certainly will fix most problems at the highest rate. I have read the stories of the expense put into diagnostic tests and coming up empty, filters being replaced, fluids being flushed, parts being added or replced to no avail. So what is the way to go?

I did have a new training belt put on at 90,000 miles or 3 months ago at a rate of $1000 at Midas (new spark plugs, various flushes, oil changes, water pump, labor). However, Mystique owners have had this problem both with belt replaced and not replaced. I have read that it can be a transmission issue, and to get it to a transmission shop so that they can run their tests, but dont turn the car off, which will lose the code. I have heard suggestions that it probably is a speed sensor/overdrive sensor/mass air flow sensor, to use a certain air filter, use a certain type of oil-5W 30, and check the runner modual control. I would just like to hear from someone that has had this problem and was able to find a solution or had a mechanic find it. I am not mechanically inclined, but have been tracking this issue on the internet and reading about it here and at contour.com. Do we Mystique owners just give up and deal with it, get new expensive parts to work around it, or get a new vehicle? I just paid the car off and was hoping to keep it for awhile to catch up on other bills. Like others in the Mystique forum, I have the back door loud creaking, the trunk leaking, the warper front dash vent cover popping up, the temperature gauge indicating an overheating (esp. in the winter), and can deal with those small quirks, but this is an issue that is annoying and frustrating, and very prevalent based on the number of stories I have read. I would like to hear from others that have this issue, how long it has been going on, is this doing damage to the car or is it just a another quirk that is a part of the Mystique (maybe why it has that name). Please, if any mechanic or Mercury/Ford solution fixers are out there, have dealt with this and found a solution, help us out.

[pharma]

Have a Dealer check to see if your getting incorrect gear ratio from the Power Control Module. It might need to be recalibrated. Below is the issue I recently had regarding my 1997 Mystique:

I have a 1997 Mystique with 150000 miles that recently had an issue recently. I was taking a 1 1/2 hour drive when I got a squeaking noise with the air turned on, and the only way to avoid the noise was to turn off the air conditioner. With 1/2 hour to go I noticed the O/D off light began to flash, but was still able to arrive at my destination without suffering any other issues.
On the return trip (w/o air conditioning), the O/D light continued to flash and I seemed to be loosing 1st gear. At stop lights acceleration seemed sluggish, but once up to speed things seemed normal, though going up hills I seemed to be loosing momentum. About with about 20 minutes left on my drive I decided to pull over since the engine really started to get jerky when driving, even though car temperatures were normal. After resting about 5 minutes I started the engine and put it into D, but the car did not move -- I then put it into 2, then 1, then Reverse with the same result. At this point I called a tow truck and went to the car dealer.
The O/D light was operating correctly once the dealer had a chance to look at it, but based on my description they performed a diagnosis and did the following:

1. Replaced bad Bell & Tensioner on Right Side.
2. Found incorrect Gear Ratio and re-calibrated the Power Control Module.
3. Replace CV Boot that Tow truck tore hole in.

So far the car is running perfectly even though it's only been a day. If the problems crop-up again I'll post here to let people know.
Hope this helps... total cost for the above was about $500.00. Power Control Module re-calibration cost about $100.00.

Pharma.

[goodburn]

Could it be the prindle switch in the transmission????
try that!

[Mark Allen]

"I have a 2000 Mystique, 95,000 miles, that just started this week giving me the same issue. When I am on the highway it pulls, jerks, feels like it is running out of gas, shifting hard, and the rpms are going crazy. I've noticed twice that the overdrive light has flashed while driving, but eventually turns off. When off the highway going slower, it will do it to a lesser degree and is not as nerve racking, but still occurs. I dont know where this problem will take me and if it will be the same as the other replies. "

Just went through this and both the fuel pump and pump relay driver died at the same time. We also had no spark when it would stall. After the relay was replaced it would start again but stall easily. Took it to the Ford dealer and had the pump replaced, it runs like a champ now.

Also see this thread....
http://www.automotiveforums.com/vbul...d.php?t=460859

[pbrittain71]

Check the acceleration sensor could be your problem!!

[pbrittain71]

I have a 1998 mystique with a v6 engine!! I had the same problem and what you discribed is what i had problems with!! Get your transmission checked before the wiring harness burns up your transmission!! I lost power going down the road and it would jerk has nothing to do with your fuel system!! I had to replace my transmission and wiring harness not too long ago!! If possible do not drive your car much on the high way but in town maybe okay but not advisable! our cars are electrical so always think electrical before anything else okay dear!!

[msvanilla]

the answer please check to see if u have a valve cover leak which is causing your spark plus to get wet

[vpedwards]

Check the ground cable going to the top battery post. The bolts might appear to be tight but that doesn't mean they are. Take the cable off and clean it then put it back on and tighten it down. Do the same with the positive cable. I bought my Contour for junk price because of this problem and even though a professional had installed the battery, he neglected to tighten it down correctly.
Vince

[98MystiqueOwner]

Hi, I have a 98 with 134K miles and I noticed right around 100K that it would occasionally sputter or seem to lose power when accelerating, as described in this tread. This problem comes and goes and I can't figure it out. I too have told my mechanic and replace lots of parts but no luck.

Then...I was digging around on these forums and I saw a crazy post where some guy said you have to keep the gas tank above 1/2 full and the sputtering will stop... I was like; "Bull sh"

Well, tonight I got in my car (1/2 tank) and started to drive home. Mostly freeway to some backroads. The whole way, as soon as I got over ~55mph it would start to jerk and hesitate when accelerating. I ended up driving about 1/2 way home and decided to try the filling up idea.

Filled up my car and man!!! no issues. It was like my car got its power back. No more sputtering, car accellerated with no hesitation. The whole rest of the drive home no problem like before, so so far so good.

I'm not sure the gas was the fix. Maybe I just needed to shut the car off to reset something. But, I'm going to try to keep my gas tank above 1/2 for the next week or so and see what happens. I'll post my results in a week.

[SimpleMan1981]

Hey everyone, I know this post is getting old and I haven't seen anything yet about the possibility of everybody's hesitation problem maybe being related to the (Power Distribution Box) a.k.a. Main fuse panel under dash? A while back I had problems with a blower motor fan (heater fan) that would work when it wanted to and then quit completely. So finally after trying every process of elimination possible, it came down to one of the main leads coming into the firewall going to the main fuse box. Needless to say it was melted to the point of F.U.B.A.R. (Which did cause a massive loss of electrical power to various main components and modules i.e. fuel pump, ignition, wipers, instrument panel etc.) so after repairing that problem temporarily nothing seemed to come up problematic until this hesitation thing started and I was wondering if it all might lead back to the corroded/burnt lead along with the harness's clip/pigtail? shorting out on bumps and might be causing the hesitation?

[Emilycarrillo39]

Mass air flow center ..they have cleaner for it r replacement part is $116.+ with a $30 core charge but try the cleaner first my car was doing the same thing changed almost everything but the mass airflow sensor now it runs like a champ

[wikidude]

Seen many post on this. Had this problem as well. I found out that the ignition coil connector went bad and not providing good contact. I let it run and would move it and it would die. Got on rockauto and got a new connector for 12 bucks. Works like a charm now.