amulla01

Hey guys I got 1999 SE model and 101k+ mileage on my car. I had this problem with my car shaking while motor is on idle mode, when drive for about 20-30 mins on my car, and then when the motor goes idle (traffic, stop lights), the car starts shaking like crazy, with the rpm needle shaking as well (dropping like .4 rpm to .7 rpm), while it does that I see that the meter lights and interior lights dim in and out. I pop the hood and see the motor vibrating too much as it was not like this before. When I drive on open roads and highways the motor is not shaking and drives normally. I had occasional stalls, once when I was standing on a light like a month ago (car still had shaking back then) and once last week when I was getting off the highway ramp, I saw the airbag and all the lights light up like it is on battery mode, and the engine went silent, but the car started up both times. I have never changed my spark plugs so I assume this might be a cause of this and also I get a code for knock sensor and maybe valve (but those ecl codes were on way before the shaking started. Oh and one thing to note is that when I put the airconditioning on, the idle goes up a bit and the shaking is not as bad but still noticeable considerably. Anyone can pinpoint as what this is and perhaps estimate on this type of repair?

amulla01

bump, no one has/had this before?

njmodi

iTrader: (4)

You have a 99 year model - notorious for failing coil packs. Not sure what other regular maintenance items you have performed, but if you don't know the history of the car, doing all the basics wouldn't hurt (plugs, fuel filter, air filter, belts, pcv valve, coolant flush, tranny flush, clean TB and IACV). Pull all the codes stored in the ECU and report back.

Your current problem (shaking) is most likely due to failing coil packs.

amulla01

I doubt that is the cause since I got brand new coilpacks installed from dealer back when the car had like 80k miles on it

madnut

one way to check is to put car in idle and let it shake, then open the hood and pull and replace the electric connection to each coil pack (it just snaps on), see if any of the coil packs doesn’t make the car shake more when disconnected if you find one like that then it is most likely coil pack, sparkplug or injector for that cylinder.

amulla01

thanks I guess I will have to try that... too bad I didnt find this website before I went to change my coilpacks at stealership about a year ago , this way I would know to at least keep all of the 6 old ones, cause I m pretty sure they were not all bad... Any other suggestions?

goldtooth

iTrader: (56)

changing your spark plugs could be another , should change them every 60k miles as recommended. Clean throttle body , IACV . costs no more than $3-4 for a can. and can do this quite easily.

amulla01

I cleaned throttle body as instructed in motorvate about 10k-15k miles ago, nothing crazy cleaning like keeping the car on while spraying. What is IACV?

amulla01

What I want to do first is to buy a current reader and test out all 6 coils. What is the normal current range of each coil? Also if only 1 coil is not working, can I just replace that one with a new one? Cause I think I read somewhere you need all 3 new ones for each side.

amulla01

Anyone know what the tightness of the spark plugs should be if not using torque wrench?

madnut

you pritty much have to be very carfefull not to overtighten, you strip that thred you will have to pay major mula to fix it :P
The plug goes in very easy till its fully in once in there just give it a lil push till u feel resistance be gentle dont use a huge rench.

StealthMaxX

I just had this happen to mine, and it ended up being the battery and alternator. The alternator's are known to fail slowly. Our alts are rated at 125 amps, the diodes inside burn slowly until it can't keep up with the charging and fails completely. New rebuilt alt and battery, good as new. Might want to check it out.

amulla01

hmmm thats not a bad idea, my alternator was kind of weak few months ago, and I had it just installed...

amulla01

But then again, if it was a weak alternator that was causing this, why does the car shake only when the engine is warmed (around 30 minutes of driving)? It has to be the fuel injectors since I m getting a code for them. Never changed my fuel filter and will try to do that tomorrow hopefully, it looks a bit tough to get to. Then the next day will go to oil change place and have my injectors cleaned chemically there for like 50$.

95maximan

clean ur throttle body. motorvate.ca

DcMaN

iTrader: (13)

sounds like egr valve. Mine had failed. When ever i would come to a stop it would shake violently, and stall occasionally when coming to a stop. But it ran perfectly as long as you were giving it gas. It also threw a ****load of codes including cam shaft position sensor, crankshaft pos sensor and a few others. You should look into cleaning the iacv, throttlebody pcv valve and the egr valve.

killcrap

iTrader: (3)

this would be the best way to destroy a 3 way catalyst.

killcrap

iTrader: (3)

so what do the diodes do exactly?

amulla01

It might be EGR valve since I had egr sys code or something for a long time, but when I changed my spark plugs recently, it went away. How do I clean the egr valve anyway?

jm272

Removing the cover to the air filter makes it easier to get to the fuel filter