1990 Legacy LS Idle Issues

[Fairtax4me]

Testing injectors at 9v proves nothing really. The ECU pulses that trigger the injectors are only 5v. Plus you have no idea what the spray pattern looks like or what the flow rate is.

 

I didn't see this anywhere, did you do a compression check yet? Just for gits and shiggles?

 

Also saw no mention that the valve timing has been checked and confirmed correct.

[blackdynamite]

well, whenever you rebuild an injector, they all seem to use a 9v to test if it is working. I didn't do a compression check yet, because it was a last resort, as was timing. And I have no Idea how to do either on this motor. I researched both, but the stuff I've found has been mixed ways to do it or super vague answers(like check your timing and make sure it's at the correct spot.....whats the correct location...i mean, I'm not stupid, but all cars are different and i want to do it correct). Same with the idle screw, i still haven't found the correct position for it...they just say same vague answer....and that is "not to touch it/adjust it"

 

How do you check the cam timing and make sure it's in the correct spot?

(If it is incorrect, how do i correct this? My Toyota's had a spring loaded tensioner with a bolt in the center, every once in a while, you loosened the bolt and it would apply the correct tension after wear. then you would tighten it back up)

 

What is the correct spot for the idle screw?

(PS: It was tampered with and is not in the correct place)

 

How do you check compression?

(I know you use a compression tester and i do have one. Is there a special way/recommended way to do it And what psi should the cylinders read?)

 

Thanks Again,

BD

Edited November 10, 2010 by blackdynamite

[wtdash]

well, whenever you rebuild an injector, they all seem to use a 9v to test if it is working. I didn't do a compression check yet, because it was a last resort, as was timing. And I have no Idea how to do either on this motor. I researched both, but the stuff I've found has been mixed ways to do it or super vague answers(like check your timing and make sure it's at the correct spot.....whats the correct location...i mean, I'm not stupid, but all cars are different and i want to do it correct). Same with the idle screw, i still haven't found the correct position for it...they just say same vague answer....and that is "not to touch it/adjust it"

 

How do you check the cam timing and make sure it's in the correct spot?

(If it is incorrect, how do i correct this? My Toyota's had a spring loaded tensioner with a bolt in the center, every once in a while, you loosened the bolt and it would apply the correct tension after wear. then you would tighten it back up)

 

What is the correct spot for the idle screw?

(PS: It was tampered with and is not in the correct place)

 

How do you check compression?

(I know you use a compression tester and i do have one. Is there a special way/recommended way to do it And what psi should the cylinders read?)

 

 

 

Thanks Again,

BD

 

Google is your friend!

Compression:

Here's one proper way, per a Google search:

-Make sure the engine has been warmed up before beginning the test, to ensure that the oil has been warmed up. A cold engine will not test correctly.

-Disable the ignition module or coil.

-Insert the compression tester into one cylinder spark plug hole at a time.

-Hold the throttle to full open position to ensure the engine gets adequate air intake.

-Crank the engine continually for at least five to 10 full revolutions to obtain an accurate reading on the compression tester.

-Record the reading for each cylinder. If any of them vary 10 percent or more from each other a problem may exist in one or more cylinders. If the variance is greater than 10 percent, specialized testing equipment may be required to fully diagnose the problem.

-If all cylinder readings are within 10 percent of each other, no further testing is required and compression is considered optimal.

 

Not sure what the NA compression reading should be, but appears having them all w/in 10% is more important than the actual #???....(Turbos compression is about 150psi)

 

Idle screw:

I don't have FSM info for the '90-91 (check THIS ), but does the TPS have white marks on the side screws? Are they lined up? If so, maybe the TPS wasn't touched and you can just adjust the idle screw so RPMs are about 700. Do it a bit and let it settle...@ least on mine it was slow to respond.

 

Timing:

Check this LINK . (Anyone know what happened to Endwrench?)

 

Here's ONE w/PICs.

 

Keep @ it,

TD

[Fairtax4me]

Warm engine compression should be something like 165 - 185 psi. (non turbo engine) I don't have time to dig through the FSM to find it ATM.

 

Timing check is pretty simple, remove the belt covers (easier said than done sometimes) on the front of the engine to expose the cam sprockets. Three bolts hold each cover on. Look through some of the timing belt threads here, there are a few with good pics of the proper marks to use for alignment. Then you just turn the crank until the marks line up. If they don't match on both sides chances are the timing jumped.

 

These have a hydraulic cylinder which applies constant pressure on the belt by pushing on a cam on the tensioner pulley. No adjustment necessary.

 

It's probably fine, but this stuff is easy to check while you're waiting for other parts.

[blackdynamite]

Thank you very much, I'll keep searching and see what i can find. I figured how the tensioner looked, it was self adjusting, so that clears that up. :]

[blackdynamite]

Still waiting on part, should be here in a few days...LOL i hate being so far away from the city... :\

 

Just the mail system in general takes at least an extra 3 days for something to ship. That might have to do with the curvy roads and 2 foot of snow....LOL