Hi i have a 98 ford explorer it gets a jerk between 40klm and 80klm its runs well at 100klm please help
Without test driving your vehicle, a jerk(ing) sensation can be a few issues to look at. Some times when an engine is under a slight to a heavy load, a secondary ignition cut out problem that will affect all cylinders for a split second could cause a sharp quick jerk sensation. A crank angle sensor that could possibly going bad can cause this issue as well. Make sure no CEL or O/D lights are on or flashing. The other jerking sensation could also be caused from the overdrive trying to engage from the transmission. Make sure the trans fluid is of the correct type (Mercon). This is usually used in most Ford applications. Make sure the trans fluid level is correct when vehicle is cold and after it has been driven for a few minutes. Trans fluid will need to be checked with engine running, so be careful of moving parts when checking. Safety glasses are also recommended when working around running machinery. If fluid level and condition looks good, you might have a bad O/D solenoid going bad which has been known to be a common problem on Ford transmissions. They are located inside of transmission above trans pan cover. Usually the solenoid is replaced as an assembly. The other cause could be a trans pump starting to get weak but in this case, it\'s not likely the cause of your description.
I also read about you over heating issues when vehicle is towing or under extreme loads. NEVER REMOVE and operate engine with out a thermostat especially in a fuel injected car! By removing a thermostat may cause an engine to run cooler......... maybe yes, but engine will start to over heat again if fluid is not regulated by the thermostat to allow enough time for radiator to remove heat from cooling system. Also if there is no thermostat in the cooling system, the ECT sensor will tell PCM that the engine is running cool and to increase fuel flow to the injectors to try to warm engine up to correct operating temperature. If PCM does not receive the correct signal from the ECT, you will notice horrible gas milage, lack of heat for the HVAC system, major carbon build up in combustion cambers and intake system. Also with the additional fuel being dumped in the engine will also cause premature CAT converter failure since it will be working overtime trying to burn the excessive hydrocarbons from all the unburnt fuel. So what I would look at is to make sure that there is proper airflow through radiator. Check to make sure that the A/C condenser does not have too many bugs and road debris causing a lack of airflow going through radiator behind it. Air flow is very important. I\'m not too sure if you cooling fans are all electric or you have one big fan that is being driven by the engine which is creating the air flow for cooling. If the fans are all electric, make sure that they cycle on and off. If it is the thermal clutch type fan, you should hear a brief roaring noise of air being pulled through radiator as the clutch begins to lock fan up when it senses that the heat coming from radiator or A/C condenser becomes excessive. I\'ve replaced many of these thermal fan clutches. Your radiator could also be restricted with corrosion build up that is restricting proper flow across radiator that won\'t be detected on light driving but more noticeable when towing or going up steep hills. That\'s when the radiator has a difficult time to dissipate the extra heat. Also I\'ve seen that if the coolant was not properly diluted with water, can also cause overheating, knocking and pinging. Hope there were some helpful tips here.
Nov 19, 2014 |
1998 Ford Explorer