Hesitation at certain revs

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Hesitation at certain revs

Postby yeatz89 » Wed May 27, 2015 11:29 am

Good morning,

I've had my 5 for a week or so now, and everything is running smoothly, even if its a 16 year old car now 8)

I have a strange issue that comes in at 2k rpm - 2.5k rpm, the car hesitates and doesn't pick up when I put my foot to the floor. Sometimes it back fires or jolts about.

Idle is completely fine and above this in the rev range the car is very smooth.

I've checked the air filter, and alls good there, I heard that the throttle body is very sensitive to cleaning, so I'm not going to touch that.

I was planning on putting it through a full service with new spark plugs and leads, but am I missing something obvious? :x

Also, I am fitting a SS backbox this evening, is it a straight fit onto the centre section, I don't need any gaskets?
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Re: Hesitation at certain revs

Postby drumtochty » Wed May 27, 2015 11:42 am

The problem here is that the car cannot use standard diagnostic equipment and getting it a full service without being able to diagnose problems will not help in certain cases as it is not caused by the oil needing changed or the radiator needing topped up.

Apart from changing the plugs and plug leads and also lifting the passenger footwell carpet, not feeling the top of it on the passenger side you will be a bit lost.

It is important to lift the carpet on the passenger side footwell to make sure there is not water in there that could damage the ECU.

The way to diagnose faults on this model of car is to get an LED and instructions from Autolink, again virtually no local garage will have this or be bothered to go to that trouble or be interested as other forum members know to their cost.

The led is available here.

http://www.autolinkmx5.com/diagnostic-f ... 6665-p.asp

You are based in Edinburgh someone local may be able to help.

eddie
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Re: Hesitation at certain revs

Postby yeatz89 » Wed May 27, 2015 11:55 am

I think I'l get the sparks and leads changed anyway, they must be pretty old and see if that helps matters.

Do I need to buy a error reader or anything with the led?

If there is anyone here based in Edinburgh with some spare time this weekend to have a look I'l be very grateful, I haven't managed to find a decent garage here that specialises in 5's.

What about coilpacks etc?
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Re: Hesitation at certain revs

Postby drumtochty » Wed May 27, 2015 12:11 pm

Coil packs would be rough idle when starting or no start at all.

Yes do the plugs and leads but get that carpet up and make sure it is dry under there.

The flashing LED is the error reader.
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Re: Hesitation at certain revs

Postby drumtochty » Wed May 27, 2015 12:22 pm

it is a Mk2 not a Mk2.5 so before mid 2000.
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Re: Hesitation at certain revs

Postby yeatz89 » Wed May 27, 2015 1:52 pm

Great, thanks I'l get that looked at over the weekend and report back.

Btw, forgot to ask, do I need to be a member to come along on the days out?

Cheers.
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Re: Hesitation at certain revs

Postby drumtochty » Wed May 27, 2015 1:59 pm

Where the sparkplug leads go into the coil pack at the back of the engine make sure the contacts are clean and not corroded.

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Re: Hesitation at certain revs

Postby yeatz89 » Wed May 27, 2015 2:51 pm

Cheers Eddie, il look at them this evening.

Got to battle with some rusted exhaust bolts this evening :)
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Re: Hesitation at certain revs

Postby paul » Wed May 27, 2015 5:43 pm

hi , think it will be your leads , but as eddie said check under the carpet just to make sure . Paul
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Re: Hesitation at certain revs

Postby yeatz89 » Mon Jun 01, 2015 9:11 am

Morning all,

Problem solved, new plugs and leads did the trick!

I also checked for water under the carpet and it all looks clean :D

Cheers for your advice
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Re: Hesitation at certain revs

Postby drumtochty » Mon Jun 01, 2015 10:42 am

Sorted now get the hood down and go for a run.
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Re: Hesitation at certain revs

Postby JimF » Mon Jun 01, 2015 4:04 pm

Hello, you are welcome to come along to some events and see if you enjoy them. If you then wanted to continue coming along we would then expect you to join the MX5 Owners club. You do not need to be a member of the owners club to participate in the forum.
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