Spark Plugs

[lexdog400]

I have a 1994 LS 400 Lexus. I have a servere miss in it like it has bad gas in it. Do you think spark plugs could make it miss like that?

[Shaft]

They could but my first call would be MAF sensor, Coil Packs, HT Leads. Have you pulled a plug and looked at the colour and condition?

And is the pressure even on both exhausts? might be build up of backpressure for failed system/cat...

[lexdog400]

Shaft, Thanks for the information. Do you think if I get a diagnostic check even though my engine light is not on that would tell me what the problem is?

[ROYT]

Suggest check all plugs and leads first, how old are the plugs?

Try looking under the bonnet ..er hood, in complete darkness, with the engine running.

Look for tracking flashes along both banks, not very easy with HT leads shrouded but you might get lucky. :)

[lexdog400]

Appreciate the comment. I'll try what you both suggest. Thanks again.

[Shaft]

Let us know how you get on. Diagnostic would be good if its not too costly. I would check the above manually first...

GOod luck.

[chris vince]

Re: spark plug check, try giving the leads a fine spray of salty water, see if the misfire gets worse at the same time also looking for the errant sparks.

regards

Chris Vince