Black spark plugs

Black spark plugs

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Discussion

zed4

Original Poster:

7,248 posts

221 months

Saturday 18th October 2014
quotequote all
I'm trying to get to the bottom of a small misfire in my TVR. It occurs around 1500 to 2000 RPM, it's only very small, but I notice it. It's also taking a long time to start.

I've removed the plugs today (so far only 4) and they're pretty black. What do you think? Are they too black, or is this normal on the RV8? I'm wondering if they're over oiled. I've got a compression tester, but it's the type you hold in the spark plug hole, so I can't do it when the engine is hot. I'll burn my hand!

DSC_6776 by danyeates, on Flickr

DSC_6778 by danyeates, on Flickr

DSC_6779 by danyeates, on Flickr

DSC_6780 by danyeates, on Flickr

DSC_6781 by danyeates, on Flickr

zed4

Original Poster:

7,248 posts

221 months

Saturday 18th October 2014
quotequote all
Just done a compression test on the offside, they were all between 190 and 200 PSI which seems nice and high, although it's hard to get an accurate result with that tester and trying to turn the ignition key on my own! can't do the nearside, can't reach the key!!

yknot

8,956 posts

137 months

Saturday 18th October 2014
quotequote all
Hi Dan, my plugs used to look like yours until I changed the 7's for 6's. Unless you are regularly driving hard then the standard heat range that TVR used will soot up. Lots of discussion on here if you search.
Can't say it will sort your slight misfire as it could be many things, but mine had that symptom until I changed the TPS!!
HTH
P

zed4

Original Poster:

7,248 posts

221 months

Saturday 18th October 2014
quotequote all
yknot said:
Hi Dan, my plugs used to look like yours until I changed the 7's for 6's. Unless you are regularly driving hard then the standard heat range that TVR used will soot up. Lots of discussion on here if you search.
Can't say it will sort your slight misfire as it could be many things, but mine had that symptom until I changed the TPS!!
HTH
P
Thanks. TPS = throttle position sensor?

yknot

8,956 posts

137 months

Saturday 18th October 2014
quotequote all
Yep. Got a replacement from Rimmers although you will need to change the plug as I couldn't get the correct type but is an easy cut and solder job.
BTW, I use BP6ES plugs now.
P

zed4

Original Poster:

7,248 posts

221 months

Saturday 18th October 2014
quotequote all
Just tested the TPS, was at 0.29v and was linear up the range. I've adjusted it so that it's now 0.33 volts at idle.

QBee

20,904 posts

143 months

Saturday 18th October 2014
quotequote all
My car went out this morning for the first time in a week. Three miles into my local town, traffic, traffic, traffic, then three miles home again.
I took out one plug, B7ECS, and have photographed it and the collateral damage. Get a crayon and draw your own conclusion.....




QBee

20,904 posts

143 months

Saturday 18th October 2014
quotequote all
PS my plugs are 6000 miles old at least.

yknot

8,956 posts

137 months

Saturday 18th October 2014
quotequote all
Glad it's not only me who ends up with collateral damage whenever I get the tools out!!! smashlaugh

Sardonicus

18,928 posts

220 months

Saturday 18th October 2014
quotequote all
QBee said:
My car went out this morning for the first time in a week. Three miles into my local town, traffic, traffic, traffic, then three miles home again.
I took out one plug, B7ECS, and have photographed it and the collateral damage. Get a crayon and draw your own conclusion.....



That's running good, now man up and don't moan about a scratch it's the nature of the game.

rigga

8,727 posts

200 months

Saturday 18th October 2014
quotequote all
Sardonicus said:
hat's running good, now man up and don't moan about a scratch it's the nature of the game.
yes nowt wrong with the plug, you're just cack handed on the tools ...

QBee

20,904 posts

143 months

Saturday 18th October 2014
quotequote all
Thanks Simon!

I love the way my Chim starts first time every time,, even though it lives outside, and runs brilliantly, even when i have just washed all the bits of hedge off the bonnet with the full force of the hose pipe.
Utterly reliable. Total joy to drive.
Every time I get the urge to super/turbo-charge or LS it, Mat Smith twists my wallet arm up behind my back, and reminds me that my car is lovely to drive and faster than my talent, so i should leave well alone and enjoy it. hehe He has driven it around Snetterton himself after he installed the V8D 5 litre lump, and he couldn't believe what a friendly beast it is to drive.

And no stupid electrical gremlins, unlike my daily Vorskin Durch Technik. In the recent rain I have had handbrake warning light on, car locking and unlocking itself 10 times a minute at 60 mph, flashing its headlights, alarm going off for no reason, front doors deadlocked while the rears were unlocked, not responding to the key, brake lights stuck on for 15 miles, etc etc. Bloody German rubbish..... furious

QBee

20,904 posts

143 months

Saturday 18th October 2014
quotequote all
rigga said:
Sardonicus said:
hat's running good, now man up and don't moan about a scratch it's the nature of the game.
yes nowt wrong with the plug, you're just cack handed on the tools ...
yes Absolutely right. As i leaned on the socket spanner I thought "when that finally comes undone my hand is going to hit the AFM clip" and it did. DOH!! Ever since my first Mini 44 years ago I have never been able to do even the simplest job on a car without drawing blood. silly

Sardonicus

18,928 posts

220 months

Saturday 18th October 2014
quotequote all
QBee said:
My car went out this morning for the first time in a week. Three miles into my local town, traffic, traffic, traffic, then three miles home again.
I took out one plug, B7ECS, and have photographed it and the collateral damage. Get a crayon and draw your own conclusion.....



That's running good, now man up and don't moan about a scratch it's the nature of the game.

yknot

8,956 posts

137 months

Saturday 18th October 2014
quotequote all
Wow!!! Now you've been told three times!

Ah, the Mini, how I remember being able to de-coke in a (extended!) lunch time!! Blood on the drawing board wasn't a problem in those days as HSE hadn't been invented, haha!!! rolleyes


Sardonicus

18,928 posts

220 months

Saturday 18th October 2014
quotequote all
Bloody phone

QBee

20,904 posts

143 months

Saturday 18th October 2014
quotequote all
Bloody phone

QBee

20,904 posts

143 months

Saturday 18th October 2014
quotequote all
yknot said:
Wow!!! Now you've been told three times!

Ah, the Mini, how I remember being able to de-coke in a (extended!) lunch time!! Blood on the drawing board wasn't a problem in those days as HSE hadn't been invented, haha!!! rolleyes
Fond memories.....I changed a clutch and gearbox. With ny skill set it took me three weeks and cost me an arm and a leg..... hehe

Sardonicus

18,928 posts

220 months

Saturday 18th October 2014
quotequote all
Bloody phone

SILICONEKID345HP

14,997 posts

230 months

Saturday 18th October 2014
quotequote all
QBee said:
Thanks Simon!

I love the way my Chim starts first time every time,, even though it lives outside, and runs brilliantly, even when i have just washed all the bits of hedge off the bonnet with the full force of the hose pipe.
Utterly reliable. Total joy to drive.
Every time I get the urge to super/turbo-charge or LS it, Mat Smith twists my wallet arm up behind my back, and reminds me that my car is lovely to drive and faster than my talent, so i should leave well alone and enjoy it. hehe He has driven it around Snetterton himself after he installed the V8D 5 litre lump, and he couldn't believe what a friendly beast it is to drive.

And no stupid electrical gremlins, unlike my daily Vorskin Durch Technik. In the recent rain I have had handbrake warning light on, car locking and unlocking itself 10 times a minute at 60 mph, flashing its headlights, alarm going off for no reason, front doors deadlocked while the rears were unlocked, not responding to the key, brake lights stuck on for 15 miles, etc etc. Bloody German rubbish..... furious
Is that using the key or bump starting laugh