Gevo

More questions as I am working on my timing adjustment today. I searched, but can't find an answer.

Question, this may be a dumb question.. i simply dont know....

The timing light flashes more frequently than the mark shows up. but when the mark shows, it is at 10 degrees, that is where I need it.

Is this how it is supposed to be? Or, is it the case that every time the light flashes I am supposed to see the timing mark? RIght now it's not even consistent. It may go 5 flashes with mark, then a few flashes without the mark and then one with mark then another 10 flashes with no mark.. etc...

I feel this may be a problem with my ignitor....... anyway. PLEASE weigh in folks. this is the first timing job i'm ever doing

YotaWoRx

Sounds like a bad timing light. Try it on another vehicle

Gevo

Yotaworx, thanks for your idea.. I checked the timing light with my friends jeep, and it is very consistent and seem to have no issues at all.

Gevo

Here are some other observations.

The spark plugs at only 20 miles were covered in dark residue. It seems like a rich condition. They looked black but I was ablr to clean the residue. So how does this, the timings situation and a rough idle when cold relate?

Gevo

Another observation. The timing light on my friends jeep was consistant AND slower at idle than the 4runner. Idle was just about 700 to 800 on the 4runner during test. But the light was going much faster than the jeep. And of course as I mentioned above not hitting the mark everytime it flashed. But did hit the mark Often. About 30% of the times the light flashed...

bone collector

any check engine light codes?

Sturmcrow

Could you post the timing light you got? Is it inductive pickup?

Gevo

no CEL codes. I did jump the te and whatever it was oints in that connecter as per fsm.

I got an inductive type... im pretty sure.. here it's this one.
INNOVA 3551 Inductive Timing Light

it was cheap.. but it worked fine on jeep. and for whatever its worth it has good reviews.

jgrant721

I'm sorry if this is too obvious but be sure you have the timing light pickup clip on the lead for the specific spark plug and not on the main line from the coil.

Jim G.

Gevo

Jim, yes jt is obvioue but ive made worse mistakes. Lol
As I left the 4runner this evening (put new heater core in) I thought of something that may be an issue. I clipped the inductor lip on the spark plug wire at the distri utor. Its pretty much in between the other 2 wires above and below it... Im thinking the inductor loop is being affevted by this... Ill retest.

Regardless of the timing.. Im getting a rough idle when cold and all of a sudden it starts working fine.

Ideas peeps.. ideas.. tps??? I tested it as per fsm but... it was not a very accurate test....

Gevo

Just to keep talking to myself here ... I wanted to share what the spark plug looked like (both from number 1 and 3 cylinders) and again, only about 20 miles on them.

It's the 2nd one on this list.
http://www.ngksparkplugs.com/tech_su...qs/faqread.asp

Now, let's one of you put all that in your experience bank and come out with my fix

combatcarl

How old are the cap and rotor? Got good separation on your plug wires? As in not running right against each other and parallel?

Gevo

Cap rotor cables and distributor are new. I've done a clean job routing everhthing.

combatcarl

Weird. I know I had some issues with my inductive light, so I dug out an old sears unit, and rigged it with a paper clip under the no. 1 plug boot at distributor, and got a better reading. I'm personally not a fan of inductive lights. Much rather have wired connection with a timing light.

Gevo

Thanks for pointing that out. TO be honest, I didn't know anything about timing until I purchased the light for this job. Hell I don't mind purchasing a non inductive one as well

First, I'll get back and set the inductive loop at a more isolated location and see what happens.

combatcarl

Yeah, I don't know if you can even find the non inductive types anymore. I got the old sears model from my dad years ago.

RJR

I saw similar behavior with the Harbor Freight light I got a few months ago. I put an oscilloscope on the output of the inductive pickup, and there are three pulses, evenly spaced, for every 2 revolutions of the engine, instead of just the one you'd expect. I think it's cross-coupling from the other two plug wires (for cylinders 3 and 5). I haven't tried moving the #1 wire and pickup well away from the other two wires, but my guess is that would help.

I think it's caused by capacitive pickup from the voltage spike in the adjacent wires. A properly done inductive pickup would be shielded to keep the capacitive pickup to a minimum. I'm guessing the cheaper lights don't do that. Might be worth an experiment to wrap the pickup with aluminum foil and ground it to the light to see if that makes a difference.

The good news is that the flash from the #1 plug, that illuminates the timing mark, is at the right time, so you can still time your vehicle just fine with the light. It's just a little harder to see the mark, with the extra flashes cluttering up the picture.

Gevo

RJR, this is an inexpensive timing light so I imagine there are many corners cut. I wish I had an scilliscope, maybe I can drive it to a friends house one day to satisfy curiousity...

Regardless, I will try to do the timing again. This time i will clip tot he spark plug wire in an isolated area and wrap the inductor clip with aluminum foil or a wire mesh or something.

I wasnt getting a steady 3 flashes to one rotation... I am pretty sure it was not a specific pattern.Ill double check anyway.

RSR

Instead of at your distributor, you should really try to place the pickup immediately above the number 1 spark plug boot. It's doable, but a pain. Just don't burn yourself on the EGR tube. The connect to battery and retry.

Sounds like your timing light is picking up multiple spark impulses.

Gevo

Thats my plan RSR. The suspense is killing me... im gonna ditch work for a couple hours today and go check it