I have the above car in my workshop, brought in with the following
Starts and runs at idle fine
As soon as you try to rev it you get to about 1500 rpm and it coughs and splutters, backfires and the engine management light flashes.

Put my diagnostics gear on it and got the error 33, Map sensor, tested the map sensor using Ford instructions, checked out ok.

Is this a commo problem?
What normally causes this?

Thanks
Eric

 

dirty lamda sensor, if fitted.

 

Phase sensor?

 

Is it standard, seens as you've tested it as per Ford's instructions and still have the ECU error lamp connected?

Vacuum or air leak? If the ECU thinks there's a fault with the MAP sensor, then there probably is. ECU's are computers and are therefore quite dumb - they can't lie, only tell you the truth as they see it.

It might not be the sensor at fault, but perhaps the wiring back to the ECU, or with the air hose connected/related to it.

The last time mine made hideous noises was becuase I'd fitted a spark lead to the wrong place on the dizzy, and another wasn't seated firmly.

 

There is no lambda sensor on this car, I have checked the wiring back to the ecu, signals at the ecu are the same as they are at the sensor.

Checked for leaks on all vacuum hoses, checked with a vacuum pump, have a vacuum gauge inline with the map sensor and that is showing apropriate readings dependent upon throttle position.

Engine runs fine at idle, if you raise the revs really, really slowly, it is fine, but imposible to drive like that, only a problem when you open the throttle normally.

With the emmisions tester connected the emmissions are all a bit high, but nothing that I see as a real problem, so that would also rule out vacuum leaks.

Any more ieas or any experts I can get some help from?

Thanks

Eric

 

i've seen this before with a dirty/ broken crank shaft sensor, but if its telling you its the map sensor it might be wise to replace that.

 

could be the diaphragm on the fuel pressure regulator,pull off the vacuum pipe and see if fuel is coming out.

 

Are you sure the car is standard?

We are chatting about chips here too. Did the car run smoothly beforehand at some point? If not the wrong chip might be trying to run greens or something??

Just a thought - as thats what mine was like before it was set up properly.

 

i suspect he's sorted it now, he posted this in July!