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Mike Kelly
Mike Kelly, Auto Service Technician
Category: Car
Satisfied Customers: 5471
Experience:  17 years experience as an auto mechanic, foreign and domestic. 5 years running my own repair business.
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my 2002 MX5 is giving me a real headache

Customer Question

my 2002 MX5 is giving me a real headache and costs are piling up. I bout it about 2 years ago and it was fine for the first year it now keeps throwing em lights. When put on diagnostic it says air flow sensor (replaced that) cam shaft sensor (changed that) cam shaft angle sensor (changed that) I have replaced all the sparks/plugs and the alternator but I still have the same problem. Loss of power, juddering, not starting very well then out of the blue just stopping completely. the car has 'eaten' the belts twice and now it wont start at all. Battery tested that's fine. all lights come and turns over but wont catch. It has a k&n filter that was on it when I bought it. I heard that this can cause problems. I am not knowledgeable enough to look after this kit properly if it requires oiling etc. Could this be caused the problems with loss of power and sensors? thank you

you need to contact me on [email protected] as the email that you have is for my paypal account and I cannot access it. thank you

Submitted: 4 years ago.
Category: Car
Expert:  Shantal-Mod replied 4 years ago.


I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.

I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you.

Thank you,


Expert:  Mike Kelly replied 4 years ago.
Hi, my name is XXXXX XXXXX I will assist you with your question.
Has the ECU ever been tested?
Customer: replied 4 years ago.
Hi mike
No the ECU hasn't as far as I know
Expert:  Mike Kelly replied 4 years ago.
This is where from the description of the issue where the problem is likely coming from. The ECU is not communicating with the vehicle properly and resulting in this issue. The ECU needs to be tested and will likely need to be updated or reprogrammed.
Customer: replied 4 years ago.

So testing the ECU is not the same as having the diagnostic done and reading the code?

Can you explain it fully to me please.

How much is the testing of ECU likely to be and do you know where I could get that done in my area? Redditch. Thanks

Expert:  Mike Kelly replied 4 years ago.
No,testing the ECU itself and having a diagnostic test done to read the codes is two separate test. The ECU test is performed with a diagnostic tool that sends commands to the ECU to see if it responds and follows commands and this determines if it is faulty or not. This is performed by the dealer or a garage that has a diagnostic tool with the proper programming.
Customer: replied 4 years ago.

The ABS light came on too. Does this have any baring on the ECU theory? It has never come on before and it was directly before the EM light came on.

Do you know how much ECU testing is approx? Thanks

Expert:  Mike Kelly replied 4 years ago.
Yes with the abs light coming on as well this confirms to me that the ECU is not communicating properly. This test will cost about 2 hours labor no parts will be needed for the test just time.
Expert:  Mike Kelly replied 4 years ago.
Let me know if you need further assistance. Thank you.
Customer: replied 4 years ago.

Thanks. And then what should I expect? Do they reprogramme it? Does that cost extra. Is it likely that it would need replacing? I just want as much knowledge as possible so they don' try to rip me off. Thanks

Expert:  Mike Kelly replied 4 years ago.
The first step is to try to reprogram it which would be about an additional hour,if the reprogram does not work it would need to be replaced however in most cases the reprogram does the trick. Also you can respond back to this question at anytime after rating positive and I will continue to grok you if you need it. Thank you.