[slickkick]

Hi,
I just bought a sidekick and I'm new to the forum. I have a 1990 Suzuki sidekick 2dr 5 speed 4wd 1.6L 8v tbi. the check engine light won't ever come on , Not sure why. The truck run good ( from what I can tell) wondering how to fix this and where to start?

 

[aquanaut20]

Replace burned out bulb..

.... Philip

 

[slickkick]

Thanks for replying
to replace a the bulb I have to take the dash apart, right?

 

[colonelhogan44]

You just have to pull the cluster. It's like 8 screws, all easily accessible.

 

[slickkick]

Sweet thanks!

Bulb was out, replaced it with the e break bulb and its all unfortunately its now on when I start the car. I will try and figure how to read the code.....

 

[colonelhogan44]

The brake light is probably just caused by low fluid level. Check that first.

 

[riley]

Your car may have a nag switch (service engine soon) if it was made for the US market. I copied some instructions from an old post by Bex I believe...



" If your car was built for the US market, then you also have a service engine soon function that works off the check engine light. If that SES function is tripped, you will be unable to get codes unless you turn it off. Presumably your check engine light remains on, even with the diagnostic fuse removed? If so, you need to find the nag switch - you should have a small panel under the steering column - remove the panel and put your hand straight down about 2-3 inches and you will find the tiniest little 'bump' - a sliding switch which you must move either left to right or vice versa, depending on which side its on now. That should turn the SES off."

 

[slickkick]

Thanks guys! I've located the nag switch and when the switch is one way I read code 12 and the other way the check engine light remains on all the time. I will be removing it today to ensure code 12 is an accurate reading and the not the light remaining on(ecm bad). Also i experienced a strange up and down idle at cold start last night with loads on. It lasted about 45 seconds then started to warm up and reach about normal idle speed(1000rmps) I'm going to leave the diagnostic fuse in start it up and see if it reads any codes during this strange up/down idle

 

[colonelhogan44]

You can just unplug the two wire harness that goes to it, IIRC.

 

[Bex]

Keep the 'nag switch' at the side where you are getting the code 12. When it's pushed to the other side and the light is on all the time, that's the service engine soon function - and with the switch on that side, you will not be able to get codes. With the switch at the 'code 12' side, remove the fuse for the dome light for a minute, which resets the computer. Now, when the key is in the on position, after you have reset the computer, the CEL should be on, and then off once the car is running.
As the car is new to you, its a good idea to do a compression test to confirm the engine timing, replace spark plugs (and wires, probably) and make sure that the plugs are gapped to .028" and not just used out of the box.
With the 1990 8v, when you start the car from cold, it should rev to about 2000 rpm for about 10 seconds, and then you should hear a noticeable drop in rpm, to about 1500 rpm, as the throttle opener at the back of the throttle body closes. The idle then slowly reduces as the car warms up. Proper warm idle is 800 rpm, by the way, which is governed not only by the idle speed solenoid, but also any vacuum leaks that you may have, as well as timing, etc. If you have an IR thermometer, if you point it at the thermostat housing, you should get a reading of about 170F. The gauge on the dash is only meaningful if the needle is pointing somewhere where it has never pointed before - my needle has pointed to 1/4 for 19 years, but the car is at proper running temp.
You can check your idle speed solenoid by having the car idle when its warm, and then turning on the headlights and heater blower on high. The idle speed solenoid should regulate the idle so that it continues at the same rpm and not drop considerably. The ISC can be cleaned with carb cleaner...carefully.
Normally, a 'hunting' idle is from the ECU attempting to control the idle, but losing control, controlling it again, etc., depending on readings its getting from various sensors, etc.
A compression test and a good service - all new fluids and filters, tranny and transfer case fluid, diff fluids, etc., should be done, as well as cleaning the EGR valve, new plugs, wires, coolant, etc., is a good place to start. Plenty of info on the forum!!

 

[slickkick]

Bex! Your awesome! Thank you for all the info everyone.
Today ill reset the nag switch but where is the dome fuse? I don't Have a cover on my fuse box also I will be making a list of things to test/clean/replace.

Test
-Compression
-IR thermometer
-fuel pressure

Clean
-idle speed solenoid
-EGR

Replace
-air filter
-fuel filter
-oil filer (new oil too)
-coolant
-new plugs, wires
-tranny, transfer case and diff fluid

So normally on a cold start ( with no loads) my rmps get up to 2300 and after about 10-30 seconds drop to 2000 and begins to warm up and slowly fall to 1000rpm after about 5 minutes. Why do you think that is? Also when its fully warm and idling (1000rmps) I turn the headlights on and the rpms go up about 500rpms and serious clicking is noticed under the hood from what I think is the idle speed solenoid or IAC.

 

[slickkick]

Oh and one more thing is the IAC and the ISC and the idle speed solenoid all the same thing??? Sorry about all the questions about questions in a newb but really want to learn

 

[Bex]

I can't find the photo on the forum of the 1990 fuse box, but it goes like this:
top row, from left to right: right headlight (10a) left headlight (10a), tail/dome (15a), stop/horn (15a), hazard (15a), cigar/radio (20a), spare, I believe (25a).
bottom row from left to right: ig-coil meter (15a), turn/back (10a), wiper/washer (15a), rear defroster (15a), heater (25a), door lock (20a), diagnostic fuse.
So the dome fuse is on the top row, 3rd from the left.
By the way, the tranny and transfer case use GL-4 (safe for yellow metal), the diffs use GL-5.

When you are reading info on the forum, there is some confusion about IAC vs ISC - Suzuki changed these abbreviations at some point. Normally the ISC is the electric solenoid - on the 1990 it is totally electric. The ISC for your car is expensive, and may be pretty hard to find. The purpose of this is to regulate the idle under load. The IAC, at least on the forum, is normally thought of as the mechanical wax pellet valve that is on the passenger side of the front of the throttle body, behind a metal plate. If you remove the metal plate, you will see an air port on the right side - this port provides additional air at cold start, and as the car heats up, the wax pellet expands to move the valve forward to block this port up. The IAC is only functional at cold start, and unless there is a problem with it, it does nothing once the car is warmed up.

Your cold start sounds fairly normal, with the exception of the 1000 rpm warm idle. This can be caused by a vacuum leak - you can check for leaks by pinching your vacuum hoses with a pliers - you should not get a change in idle on any hose that you pinch - if you do, then either the hose, connection, gasket, etc., is leaking on that circuit. Frankly, unless you find a definite leak, I wouldn't be tremendously concerned about a slightly high idle. However, you advise that with the headlights on, your idle rises and you hear a clicking - this is most probably the ISC solenoid. If you stand on the passenger side of the engine, it will be pretty much in front of you - easily identifiable if it is clicking away like mad. If you disconnect and remove the solenoid, you can hook it up to 12vdc (a poster here actually got it to work with a little 9v battery) and watch it work - there is a little plunger inside that vibrates at something like 20x a second - this plunger can stick, etc., especially after years of service. You can get carb cleaner and carefully clean the solenoid so that the plunger is free to vibrate and not stuck in either the open or closed position. However, when you remove the ISC, if you shake it and it's rattling, it's pretty much gone.

 

[slickkick]

Great info I think i get it now but I went to look up what the ISC and the IAC look like and found this

1990 SUZUKI SIDEKICK Fuel/Air : Idle Air Control (IAC) Valve Auto Parts

It clams that the IAC is an electric solenoid witch is confusing cuz you say the ISC is the electric solenoid?

 

[Bex]

Like I said, Suzuki changed the terminology at some point - for the early Sidekick's they call the solenoid the IAC. Later, they change this to the ISC. For the purposes of the forum, it's best to indicate whether it's the IAC/ISC thermal (the wax pellet valve) or IAC/ISC electric (the solenoid), so there is no confusion

 

[slickkick]

What is the compression suppose to be?

 

[Bex]

On the 8v, it should be about 170psi on a warm engine - floor the gas pedal when you crank for compression, for best results.

 

[slickkick]

I am reading about 70 on all. What does this mean?

 

[colonelhogan44]

That means you probably don't have the throttle open during the test.

 

[Bex]

Hmmm....possibly not. I found that without the gas pedal floored, the difference was about 20psi on each cylinder.

If you're getting about 70 psi on each cylinder, (and its best to post your results cylinder by cylinder, confirming that your gas pedal was floored, your engine was warm or cold, all plugs out, etc) then it would seem to indicate that your timing belt is not timed properly - that the wrong marks were used when doing the belt or, worse: that someone removed the center crank pulley bolt when doing the timing belt, and didn't torque it properly when they replaced it (94 ft/lbs) and your crank keyway sheared.
I would get a torque wrench and confirm that the crank bolt is torqued properly (if you find that it is, breathe a sigh of relief). And if it is, and you confirm that you did the compression test properly, I would check the timing belt.