How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask sebastian manrique Your Own Question
sebastian manrique
sebastian manrique, Auto Mechanic
Category: Car
Satisfied Customers: 649
Experience:  Director Ejecutivo at Multiservicios Cruz de las Mercedes
100564933
Type Your Car Question Here...
sebastian manrique is online now

Very intermittent issue with MX5 2000 MK1. Feels like I have

This answer was rated:

Very intermittent issue with MX5 2000 MK1.
Feels like I have run out of petrol and there is fuel starvation.
When I remove the petrol cap there is a real hiss if there is a vacuum in the the fuel system. It then will not start.
If I wait 1 hour then it starts no issues and runs like a dream??

Hello, I am Jose Sebastian. Your mechanic automotive expert, It's a pleasure to me to attend your question. Thank you very much for trust in just answer.

Dear customer, thank you very much for contacting us, let me explain to you, the fuel tank stores a lot of gases, any fuel, especially petrol when it is enclosed.
The fuel tanks have a system to leave the tank without losing fuel by means of an EGR valve, you have all the symptoms that this valve is defective, my main recommendation is to start with a computerized diagnosis, rule out the error codes that may be generated by some sensor that is defective, if there are not error codes, proceed to maintaince to the fuel system, clean the tank, replace the filters and clean the injectors, and then if all this does not help in your problem, you should proceed to replace the EGR, it is better to rule out these aspects i mentioned before because they are cheaper.

Have you understood me dear customer?

Customer: replied 1 month ago.
Why would it be egr? The engine failt light never comes on at all?
Customer: replied 1 month ago.
Also engine has only done 32000 milles.

As i indicated dear customer, as you told me, there is a vacuum that should not be produced when opening the fuel cap, this is generated because there is pressure inside the tank, the only component that causes pressure in the tank is the EGR, so this indicate me that you have a problem in it.

Just as you indicate, the feeling that the vehicle has run out of fuel is a symptom of drowning in the EGR.

But not necessarily only the EGR can be causing the failure in your vehicle, I would like to know what have been tried in the garage, have they checked the fuel pump? the fuel is arriving to the injectors?
At first, i observed that you commented that you feel as if you run out of fuel. therefore, have they checked the spark in the coil? Is the CKP sensor or crankshaft sensor working well?
The most obvious damage I see is in the EGR valve, but if the technicians have not reviewed the aforementioned, they should start checking this.
Have you understood me dear customer?

Customer: replied 1 month ago.
I have purchased a gadget that allows me to read engine codes. It has p1345 camshaft sensor error in the ECU.
What is this?I assume this means that the running out of petrol was incorrect and I need to replace this sensor?

Dear customer it was really good to make the computerized diagnosis!
The camshaft sensor is in charge of determining the operation of time and distribution. When this sensor is defective generates certain types of failures, many times it is solved replacing it But to avoid additional expenses replacing the sensor, the first check the condition of the connector and the wiring of this sensor because it is very common that because the place where it is located so close to the engine, wires and connector tend to burn because of the high temperature to which it is subjected. It is always advisable to verify this first, before proceeding to replace the sensor. Also this sensor works with a very important sensor known as the CKP. The CKP manage the spark of the coils, if this sensor is in poor condition or the communication is wrong the car does not turn on. For this reason it is always good to start with a computerized diagnosis before doing any type of work has been very wise in making that decision dear customer I apologize.

Hello dear customer, i hope you are ok.
Did you solve your problem?
Is there anything else i could help you?
I also would like to remind you to rate my service by selecting from the 5 stars at the top of the screen because in that way you help me grow in the platform.
Thank you very much.

Customer: replied 25 days ago.
it has been fixed by replacing the camshaft sensor indicated aa faulty by ecu.

Great dear customer! i am glad you sort out your problem!
Regards, Sebastian.

sebastian manrique and other Car Specialists are ready to help you