Rolando

So I recently changed my spark plugs they where in bad condition car is at 93k the car never acted weird or anything just changed it since the original owner never did at 60k. So I put brand new plugs, when I installed them everything was good and still is but this is the problem. When I start up the car when is cold the car revs to 1500 goes back down to 1000 then bak up to 1500 then settles at 1200 then it doesn't do it no more and the car runs normal. It has never done this in the past so that's why I'm a lil worried I changed the plugs 8 days ago and it has done this 4 times at cold start up the rest of the times it just starts up normal. I checked all the lines and hoses of the car everything is fine.

The plugs I installed where pulstar plugs be-1. I found a deal for 6 plugs only for 100 bucks so I said why not. The car read before 13.6 mpg now it reads almost 17 mpg. I recently reset ed the computer how it said to do on the plugs so I don't know if the reading are accurate but I mention the plugs incase it has something to do with the start up. I don't think a cylinder is misfiring because I have no check engine light or anything on. So what you guys think?

flektone

iTrader: (1)

Im not to sure of the brand of spark plugs you bought. The only respectable brand ive ever delt with are NGK. But plugs arent something you wana go cheap on, just make sure they are a good brand. As far as the revs mine does that to. Shoots up to 1500 almost 2000 one time when I turned it on. But that was for like 5-10sec. I think the resting idle is around 1000 for me. Whats does or did your car idle at?

uz07lex

iTrader: (14)

Ive had three cars with two of them with high miles on them and they all on start up idled a lil high. But then went down. My IS has 55k on it and does idle at 1500 and on really cold days it goes up even more but then goes back down.

2slow

iTrader: (5)

Weird how? Rough idling?

2006Onyx

I haven't used the pulstar plugs before, so I'm not sure if they are like the bosch platinum +2 / +4 plugs (and can't be gapped), but if they are gappable, did you check to make sure they were gapped right?

I've found that some cars can be picky in terms of idle quality with the plug gap, and also the heat index of the plug.

Rolando

They come gaped at 0.40 I believe out car is at 0.43. But I don't have no rough idling it jus happened 4 times where the rpm when to 1500 dropped to 1000 then back up to 1500 then stayed at 1200rpm also this is only on cold start the car runs normal but it has never done dat on start up.

Pnuge88

iTrader: (1)

Dude its normal my car always does that and i know because i watch it every morning when i go to work. It revs up high to like 1700-1800 and i wait till it drops to 1200 before i switch into drive. It only takes a few seconds. 5-10

Rolando

Lol no let me explain in a better way. Before I changed my plugs the cars used to rev high then drop normally I understand that is normal. But since I changed my plugs in cold start up it will rev high drop to 1000 then go back up to 1500 drop then go up to 1200. Then it stops. And idles fine. The only way to describe how it looks is like if the cylinder is misfiring but I know is not because the engine runs strong and fine and I don't have a cell light. So I wanted to know what could it be that causes the car to start up like that sometimes or an opinion on what it could be.

2006Onyx

Since it's right when the car is cold, I would only look into sensors that the ECU is using when it's in open loop.

I haven't dug into the ECU stuff on this car yet, so I really can't say what they are. It is possible you might have a small vacuum leak that the computer trims away using the idle air control valve (If these cars have one). That would explain the oscillations that seem to get closer to the ideal idle of 1k.

If the ECU can trim whatever is wrong enough that it doesn't hit an absolute max/min, it usually won't throw a CEL because it figures it's normal wear and tear.

...Again though, all of this is general OBD2 stuff that I've dealt with on other cars...

2slow

iTrader: (5)

It has to be spark plugs or anything you touched while you changed them.

Check the gap again. If one is too far,it'll make it flutuate from 1500k -1000k then back again.

Even though they come pre-gapped, it's always best to check yourself.

Koz

Do yourself a favor and get those plugs out and replace them with NGKs or Denso!

Koz

flektone

iTrader: (1)

what he said. and always check the gap out of the packaging. they are handled by people and transported around the country until it makes it to the store. It could easily get knocked out of position

tC_demon

Plus+1...Go to Sears and get your self a proper set of gap gauge (not the circle ones) around less than $15 and make sure they are properly gap...to toyota specs, and make sure they are torque correctly. Have you tried to put the old ones back to see if it does it?

Rolando

I never checked the gap but they come at 0.40 guess I'm going to have to check this weekend. Also the old plugs are sooo in such bad conditions I wouldn't put them back in the car, when I saw the plugs I was truly amazed on how bad they where and how strong the car pulled.

Maybe it was a mistake to buy pulstar plugs but the car seems to run fine and wit power, its just on the cold start up that the revs go up and down a good 4 times before it settles and everything runs normal.

But this weekend I'm going to make sure I do that as well as clean the throttle body and maf sensor.