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Mike Kelly
Mike Kelly, Ford Mechanic
Category: Ford
Satisfied Customers: 5470
Experience:  17 years experience as an auto mechanic, foreign and domestic. 5 years running my own repair business.
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Ford Fiesta finesse 2003 1400 cc petrol Engine is misfiring

Resolved Question:

Ford Fiesta finesse 2003 1400 cc petrol
Engine is misfiring on slow revs when ticking over but runs great when rev'ed up or being driven.Local garage has changed all plugs HT leads and injector on no4 cylinder(the one they thought was causing the problem)but no joy.The inline fuel filter was also changed as it was found to be dirty.The emisions test showed that car would pass test when engine accelerated but not when idling.
Submitted: 3 years ago.
Category: Ford
Expert:  Shantal-Mod replied 3 years ago.
Hello,

I'm Shantal and I'm a moderator for this topic.

We have been working with the Experts to try to help you with your question. Sometimes it may take a bit of time to find the right fit.

I was checking to see if you had already found your answer or if you still need assistance from one of the Experts.

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Customer: replied 3 years ago.


I'll keep waiting

Expert:  Mike Kelly replied 3 years ago.
Hello, welcome. My name is***** will do my very best to assist you with your question. I apologize if you have been waiting long for a response.

Are there any type of warning lights coming on at all?
Customer: replied 3 years ago.

Sometimes the engine management light would come on and then after a few miles would go off but has'nt come on for a while.When testing with emisions tester it would fail the MOT on slow running but once revs. increased a little it would pass test.

Expert:  Mike Kelly replied 3 years ago.
The issue that you are having really is consistent with a weak fuel pump that has an internal failure of the diaphragm. The next step would be to check the fuel pressure cold, then hot and while driving and also check to see if the pump is holding pressure and not leaking down.
Customer: replied 3 years ago.


Thank you for that but how do I check the fuel pressure and especialy whilst driving?Is there special equipment that is required in order to check the fuel pump? Is it an expensive job to change pump if needed?.Thanks again Mike at least I'm getting some help.

Expert:  Mike Kelly replied 3 years ago.
The fuel pressure is checked with a diagnostic tool that is connected to the vehicle this will monitor the fuel pressure while driving and at cold temperature. As far as the cost that really depends on the shop performing the job. Each shop is different.
Customer: replied 3 years ago.

Thanks Mike One last question Is the cost of a new pump reasonable and normally a straight forward job to change?.

Expert:  Mike Kelly replied 3 years ago.
Yes it is about a 2 hour labor job and the part is not to bad expensive. Thank you.
Mike Kelly, Ford Mechanic
Category: Ford
Satisfied Customers: 5470
Experience: 17 years experience as an auto mechanic, foreign and domestic. 5 years running my own repair business.
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