Spark Plug Change Problems

[Oliver Hardy]

Being a DIY expert and worlds leading mechanic I usually take my cars to the garage to be fixed, but my MR2 started misfiring a little and reading forums was advised it might be spark plugs - so decided to change them myself, how hard can it be?

It wasn't change went easily and I went to start the engine, already congratulating myself on fixing the car, first time ever and the car won't start, doesn't turn over, clicks once and nothing.

So anyone who isn't as brilliant as me help me out and advice me on what might have done wrong?

[Sheepshanks]

Flat battery?

[Jambur]

Leads on in the right order? Properly connected? Normally do one at a time to avoid confusion. Wrong plugs?

[C5_Steve]

I was going to ask if you'd disconnected the battery and forgotten to reconnect it, but you say it clicks...

Nothing you've taken off should stop it cranking so I can't think of what else you might have done. Hopefully someone who knows the layout of the MR2 engine bay can suggest what you've accidentally unplugged, I'm assuming as it's quite cramped it's something you've done my accident!

[finlo]

Plug too long and hitting the top of a piston?

[Oliver Hardy]

Thanks for all the suggestions, but the engine just does not turn over, hear the starter motor click once. The battery is at 70% which I am guessing is sufficient to at least attempt to start, but put it on charge.

[catso]

Another fine mess eh?

Sounds like a flat battery to me, is it just a single click or a click, click, click...?

[Sheepshanks]

finlo said:

Plug too long and hitting the top of a piston?

I did wonder about that but you’d sense some effort to turn the engine over, wouldn’t you?

If it’s not the battery then it might be worth the OP removing the plugs and seeing if the engine will turn over if not absolutely certain that the new plugs were identical to the old ones.

[E-bmw]

Some people are seriously over thinking this!

It is either a flat battery or a lead has come off the battery/engine earth/chassis earth and not back correctly.

How are you saying it is at 70%?

Does the voltage drop when you try to start it?

[Sheepshanks]

It’s unlikely but it’s even possible the starter could have chosen that moment to fail.

[Oliver Hardy]

catso said:

Another fine mess eh?

Sounds like a flat battery to me, is it just a single click or a click, click, click...?

Yep, fine mess like most of my DIY

One Click

E-bmw said:

Some people are seriously over thinking this!

It is either a flat battery or a lead has come off the battery/engine earth/chassis earth and not back correctly.

How are you saying it is at 70%?

Does the voltage drop when you try to start it?

If the lead had come of surely there would be no power yet all electrics work.

I have a meter that connects to the battery to indicate the charge state. I will check the voltage tomorrow

Sheepshanks = The plugs are identical, it does sound like a starter doesn't it?

Many thanks for the answers

[Sheepshanks]

Oliver Hardy said:

If the lead had come of surely there would be no power yet all electrics work.

I have a meter that connects to the battery to indicate the charge state. I will check the voltage tomorrow

Sheepshanks = The plugs are identical, it does sound like a starter doesn't it?

Many thanks for the answers

Well, it's just guesswork to diagnose these things remotely.

Is the starter power lead (ie the main cable that runs the starter) fused on these cars? Googling suggests not, but you never know.

The click you're hearing may be something else and not the starter solenoid. Have you checked the starter circuit - Google says AM2 fuse (but don't assume that's correct)? Do you need to press the clutch - are you having a brain-fart and forgetting?

[E-bmw]

catso said:

E-bmw said:

It is either a flat battery or a lead has come off the battery/engine earth/chassis earth and not back correctly.

If the lead had come of surely there would be no power yet all electrics work.

Now read the full line, not just a few words of it.