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Engine Misfire on Ford Mondeo

I have a Ford Mondeo MK4 2009 2.3L, I have 2 main issues within this vehicle.
When driving more than 5 minutes the engine misfire and suddenly the car got not power and I have to use Tiptronic Transmission so the vehicle will not lose power completely on the road plus the engine temperature raises to maximum (120c) but not really, Probably a problem within the sensors.

Second problem would be that my speedometer is not working and it is always on 0 km/h. In addition, all of the warning lights turn on. The only thing that works well is the fuel gauge.

Any ideas what would be the problem? I am willing to replace the intake manifold runner control valve for
resolving the first problem, for the second problem I checked the fuse box and everything seems to be okay. What would probably be the problem with my Ford?

The list of the potential problems is probably in the hundreds.
You need to have the stored OBD trouble codes “read” by a mechanic, or at least by an auto parts store. After you get the codes, then you can come back here and post them for some specific advice.

In the meantime, if one of those warning lights is for low oil pressure, I would suggest that you have the car towed to a mechanic, rather than driving it.


Thank you for the quick answer
My father took the vehicle to a mechanic and he done that code reading process, The mechanic said
that he found nothing. Tomorrow or soon I will take the car to an other mechanic so he will tell me what is the problem but unfortunately 2 different mechanics had no answer for me… Do you think that replacing the intake manifold control runner valve worth a try?

I think you need to get the speedometer figured out and fixed first.

With out a speedometer the computer doesn’t know the car is moving and is limiting engine performance.
Probably also limiting RPM’s to 3000 or less.


Exactly. it is limiting the RPM to 3000 precisely and switching to Tiptronic Transmission does the job.
Btw, engine is new, gearbox too. So the speedometer is the problem here?

Many cars now have a VSS Vehicle Speed Sensor and if it’s not working a lot of weird stuff happens.


The VSS Vehicle Speed Sensor is within the speedometer?
An electrician offered me 220 bucks to fix the whole speedometer, I mean the dashboard.
Should I go for it?

Speed sensor should be on the transmission.

And may be something as simple as not plugged back in when doing the transmission swap.


concur w/above, the first step is solving the speedo reading zero problem. or at least verifying the computer knows the actual speed. on my corolla the speed sensor is in the speedometer itself, but newer cars the sensor is in the transmission, and the speedometer is just an actuator driven by the computer. If that’s the case in your car and the speedometer is not the problem then the computer thinks the car is not moving and you’ll never get it to run well until that is fixed. If you want to replace something, replace the VSS in the transmission before diddling with the intake runner valve. Better to do/seek a proper diagnosis. The signal from the VSS can be inspected via a scan tool or an o-scope for example to verify whether it is correct or not. How you do that w/a moving car on the road, don’t know, but I’m pretty sure it can be done.

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Btw, engine is new, gearbox too.

This statement about the engine and transmission mean that someone was busy under the hood of this vehicle… Whomever performed an engine and trans swap has opened a great many avenues toward potential problems. The list is enormous, but common items are ground wires not reinstalled correctly or at all… computer incompatibilities, electrical connections etc… just to mention a few…there are plenty other ways to screw up. If you paid to have that done…take it back to them.

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Did I mention that all of the warning lights show up? is the VSS related to warning lights also? because if not
probably the problem is within the dashboard…

I believe that a defective VSS will cause the CEL to light up.
And, on some cars, when the CEL lights up, many of the other warning lights will put on a light show,

The VSS will definitely throw a code for any malfunction. This vehicle has had an engine and transmission swap…and now the entire dash is lighting up, not throwing codes, overheating or not overheating with engine misfires and the OP is seeking to repair this via an intake manifold runner control valve and a VSS sensor? Whoa… Hold the phone Chuck.

Everything was disconnected and another engine and trans installed… There can be so many reasons this is happening and it surely is not one sensor or item. This is a systemic issue…go back through the wires and plugs and grounds etc

Did everything work normally for a period of time and then this condition presented itself? How did we get to this point in time? Please begin the story from the “New engine and Trans” install and then bring us to this issue. It will help everyone get a handle on this…if that is at all possible.

Clicking on who ever Donna is will show that they have been banned . Thank you Carolyn.

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about friggen time…+1 to the thanks to @cdaquila

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Apologies. I thought I had banned the account already, but it appears I didn’t save my settings. It went on too long.