running issues

[matt86]

Hi

I bought a m20 2 litre convertible 9 months ago which had been off the road for 10 years.

When I received it there were many mechanical issues from being stood.

It wouldn't start and I fitted new ECU, fuel pump and sorted a bad connection too the fuel pump.

I also carried out a full service including:

Plugs
Rotor arm
Distributor
Cambelt
Drive belt
Fuel filter
Oil filter
New oil
Fresh fuel
RedEx

The car now starts fine, idles fine, but occasionally when I give the car more than 50% throttle or go up a hill it sounds/feels like its starved of fuel and comes to a standstill, but then works OK again when left for a bit. Its also blown one fuel pump! And this fuel pump and the new one are buzzing but not all the time.

I'm wondering if the fuel pressure regulator is bad and is causing back pressure on the pump, is this possible?

I was planning on changing this next.

I can only think of bad connection to the pump AGAIN or bad regulator. Also can the ejector valve in the fuel tank cause this issue or problems with the tank itself?

[matt86]

Thanks will. Good advice. I will give this a go. Thanks again.

[Brianmoooore]

You need to check 2 things initially.

Make that three!
What does the rev. counter do when the problem occurs? Drop to zero immediately, or slowly drop as the engine revs. drop?

[matt86]

You need to check 2 things initially.

Make that three!
What does the rev. counter do when the problem occurs? Drop to zero immediately, or slowly drop as the engine revs. drop?

Hi Brian,

It slowly drops and the more I push the pedal down the quicker the car stops and the more it struggles, it also appears to be worse the longer I've been driving. I did also consider air leaks or a faulty air flow Meter.

Thanks

[matt86]

Also in the colder weather we've been having the car seemed better today when I drive it although after 30 minutes or so when the engine was at 85-90 degrees there problem got worse, although this could be coincidence as it seems to be more of an intermittent problem. There is no regular sequence to when it happens although is definitely worse when under load.

[Brianmoooore]

That rules out a few possible electrical faults, including, most importantly, a faulty crank position sensor.
The fuel pressure check is the test that needs to be done. Cheap kits are available on ebay for around £10, but you need a six inch length of high pressure fuel hose to connect it up to an E30, or a considerably longer piece if you are going to be able to see the gauge while driving.

[matt86]

That rules out a few possible electrical faults, including, most importantly, a faulty crank position sensor.
The fuel pressure check is the test that needs to be done. Cheap kits are available on ebay for around £10, but you need a six inch length of high pressure fuel hose to connect it up to an E30, or a considerably longer piece if you are going to be able to see the gauge while driving.

Thanks Brian,

I've already changed the crank sensor for another used one and cleaned it too. Forgot to mention that.

My view is an issue with the tank or tank ejector valve, fuel pressure regulator or bad connection\earth to the fuel pump.

So I think I need to eliminate these. I will also buy a fuel pressure check kit.

[matt86]

I've just got a fuel pressure regulator, so I'll change that and see how it goes. After that I'll check the fuel pressure, fuel pump voltage and the tank

[matt86]

I've changed the fuel pressure regulator now too and still no joy.

If the car ha been off the road 8 years is there a possibility the injectors are clogged and would this cause an issue like this?

It feels to me like more of a fuel issue than electrical.

One other thing is that my idle control valve is making a high pitched buzzing noise when the ignition is on and when I touch it it's vibrating.

Is this normal and would this cause intermittent running issues?

Thanks

[matt86]

Getting the injectors serviced is the sensible thing to do even if they are not the cause of the issue, it is money well spent.

Idle valve does buzz, so sounds like yours is acting normally. Clean the valve in brake cleaner or similar to make sure it is properly free.

Thanks will I might take this out myself and give them a good clean.

[matt86]

Unless you have the proper equipment to clean and set up the injectors, you are really wasting your time. They are internally cleaned (normally sonically), then set up so the spray pattern is right, they are injecting at the specified rates and balanced against each other.

OK thanks will I'll try and find somewhere to do it for me then or find some new ones.

[matt86]

Injectortune on this forum does it, has done probably hundreds for zone members.

Thanks will I'll ask for a quote

[matt86]

Ive changed the fuel filter again this weekend. Changed it around 500 miles ago only 2 months ago anyway. When I removed it dark brown fluid came out of the old filter which has only done 500 miles and fitted new. I've checked my fuel tank which I purged the old fuel out of by linking pins 30 and 87 on the fuel pump socket. I've gone through 2-3 fresh tanks of fuel and put redex in. The car before this had been stood 10 years but I have changed all electrically
And fuel related parts with new and carried out a full service.

But I looked today after I changed the fuel filter again and the fuel tank looks quite corroded at the bottom and the fuel is brown the same as whaT came out of the fuel filter

Do I need a new fuel tank and could this be the reason my car is intermittently running crap because the flow it getting blocked by small rust particles?

Has anyone heard of this happening with e30s in the past?

Thank you

[matt86]

e30 fuel tanks rusting? Never heard of it before...




get a new tank. your fuel will love you for it!

Thanks will. I would imagine there is a fairly good chance that this is what's causing my running issues too?

[matt86]

Your fuel filter should prevent the fine particles getting to the injectors, but they will quickly block the filter, preventing the necessary volume/pressure required to run the injection system properly.

Put a new filter on and see if this improves or sorts your problem.

This is what I did today. This is my second new filter in 800 miles. I suppose it is still possible!e that the two things aren't related although I've changed everything else apart from the injectors, throttle body and throttle position sensor.

[matt86]

One other thing I haven't changed is the blue temp sensor that goes to ecu