mlevk

Hi , anyone else try the Bosch Platnium +4 plugs ?

I replaced mine and I noticed that I seem to get a
slight "skipping" or "missing" during steady cruising speeds.
anyone else had this problem?

I put back the OLD Nippon Denso and it seems to
have went away.

Maybe they gave me the wrong plugs ? wrong heat range
or the "GAPS" are not large enough ? At least the BOSCH
are "money back , satisfaction gauranteed"

Any thoughts or experience ?

additude

I have had the Bosch +4 in mine now for about a month and haven't noticed your problem. It's possible you received a defective plug. You can start swapping them back in. Do 4 on one side and see if you have the problem, then if you don't have it replace 2 of the remaining 4. If you have the problem swap one of those, if you don't have the problem then swap the last two to find which one.

It is possible that you have an ignition system problem that is being aggravated by the new plugs. Such as it might take a little extra energy to jump the gap in the plugs and that's just enough to leak through a weak wire and spark to ground ocassionally causing misfire.

If you suspect that to be the problem then you'll have to swap a known new plug on that wire to verify the wire as defective.

Find out if you have a bad plug, if you do replace it. I have not had any problems with mine and it has smoothed out the idle.

mlevk

That sounds like a great eliminating sequence.
I'll try that this weekend.

additude

Let me know what you find out.

Slexus

I am glad I found this forum. I think I have same problem. Engine misfire intermitenly right after I replace Nippon Denso with Bosh Platnium+4 on my 94 Lexus LS400. I am planning to buy Nippon Denso and will replace them on the Memory Holiday next week. I will report back the results.

additude

Well, I have them in my 97 LS400 and it's not a problem.

It may be possible that you have the wrong plug. Maybe you have a cold plug or hot plug.

Just double check.

Lvangundy

The same thing happened to me when I tried Torque master plugs.


After the problem was fixed - https://www.clublexus.com/forums/sho...ghlight=torque

When I took a trip to toruqe master offices -https://www.clublexus.com/forums/showthread.php?s=&threadid=62124&highlight=torque

When I was trying hrd to figure out why my engine was stuttering- https://www.clublexus.com/forums/sho...ghlight=torque

Before I noticved the problem was related to the engine , not the transmission. - https://www.clublexus.com/forums/sho...ghlight=torque


Stick with toyota OEM plugs. Unless there's a way for the aftermarket plugs to NOT make the engine is-fire then I'll try them.

persian451

I have NGK plugs in my car and they work fine... no misfires..

Slexus

Hello Everyone,

Happily to report back in my progress regarding Engine Misfire intermittently. I promised myself to replace all 8 spark plugs to ND on my 94 LS400 on Memory Holiday next week. Well, I could not wait till the holiday, I went ahead bought Nippon Denso PK20R11 original spark plug then replaced them all.

Bamm, Engine running like normal no more misfire at least at this moment!!! "No more crosss reference Spark Plug for my car". I will report back if there is any problem.

Thank you, the Forum Owner and Everyone for there input. This is wonderful way to helps other.

persian451

that should cure your problem man.. because the gaps can make a big difference.. only trust Denso plugs from Toyota/Lexus....... i have NGK double platinum in my LS4 and it runs very well... I believe NGK is the only close match to those of Denso..

97LS400

What gap are you'all setting the NGK & ND plugs to? I went .035 and think it is too small. Car runs perfect but seems a bit down on power + 1/2 mpg off.

I know it's a pain in the *** on our LS model but don't forget to clean the contacts in your distributor caps and the roter face each time you change plugs. I actually clean mine every other O&F on all the "family cars (97 LS400, 97 ES300, 98 Civic, 93 Accord) I maintain. It can makes a HUGE difference in smooth idle and throttle response. Just take care not to get any body oil inside the cap and clean all the flakes of oxidized metal out with compressed air and/or a soft cloth.

Shaffer

Did anyone's car have an occasional miss only at idle and rarely while driving? The 90 LS400 I am considering has an occasional miss at idle and want to be sure it is nothing major before I buy it. Thanks.

additude

Is it a private individual or a dealer that you are buying from?

It could be a lot of things, some simple and some not. However your car should never "Miss" a beat unless there is something wrong.

First place to start is the ignition sysyem. Plugs, wires, rotors and caps. More than likely it's the plugs or the wires.

Anything beyond that and your going to need a mechanic to troubleshoot and fix if your not one yourself.

You might try running a couple of bottles of Techron (fuel system cleaner, Autozone) through it also.

Good luck!