setting idle

[x3rikaa]

ok so NOW i know youre supposed to disconnect the tps before you start messing with the idle screw. except i didnt know and i just went ahead and adjusted it anyway without disconnecting the tps AND with the engine running. what kind of problems does this cause? can i jsut disconnect the battery to reset the ecu?(if that helps any).

i initially did this because my idle was/is at 1500 warm and messing with the screw did NOTHING. im pretty sure i have a vac leak (which i thought i solved) because when cold, the idle is at 750 RPM. when warm, it is at 1500 RPM

its a 91 dohc, previous owner removed emisiions and i: reconnected fpr hosecapped 3 pipes in the backside of the intake manifold(near firewall)capped 4 pipes on the front side of intake manifold(right beneath throttle body)

is there anything else i missed that i should have blocked or capped off? idk where the vac leak is coming from (if my problem does sound like a vac leak)

[Wc240]

first id look at a vac diagram to make sure what was disconnected. alot of that stuff even capped will f### with your idle.then, get the fsm, itll show you how PROPERLY to reset and adjust your base timing/idle

[Gabes13]

Check your tps. The whole iacv unit becomes useless if the tps isn't working properly.

[x3rikaa]

okayy, well how do i check the tps? i know you need to check the ohms or something with a multi meter but where do i put the probes to check?

[x3rikaa]

first id look at a vac diagram to make sure what was disconnected. alot of that stuff even capped will f### with your idle.then, get the fsm, itll show you how PROPERLY to reset and adjust your base timing/idle

i thought you are supposed to cap off all openings? why would it being capped mess up the idle? just wondering cuz idk.

[Wc240]

i dont like to. your motor uses vacuum to control different things. i was saying look at the vac diagram to see what is capped off at bypass. a last resort would be to connect everything right(like factory) and then see whats goin on with your idle. also, in the FSM, in the step by step how to of setting base timing/idle, it tells/shows you how exectly to check and adjust the tps

[Gabes13]

okayy, well how do i check the tps?

There are a couple of ways, and you should try them all.

Start off by checking the resistance between terminals e and f



I think Chiltons recommend it to be set some where between 0.4 ohms and 0.7 ohms.

If your tps doesn't read anything between that, loosen the 2 bolts that hold the tps to the throttle chamber, and slightly rotate the tps to report the specified ohms. If you can't get the tps to put out the correct resistance, replace the tps.

If/when your tps emits the right resistance, check the resistance while opening the throttle body. If the resistance does not increase (or decrease if you mix up terminals e and f on your multi-meter) then replace the tps.

On your ecu, run mode 3 and check for any codes you may be throwing. If code 43 (tps error) is present, check the connectors and make sure that they're all snug and fit.

If code 43 doesn't show, run mode 4 on the ecu. Depress the gas pedal, if the light (green or red, I don't remember) doesn't come on while depressing the gas pedal, replace the tps.

I think that's everything.

If you do all these and everything clears, then your tps is fine and your problem lies elsewhere.

gL

[vancouverbc]

look up idle in tutorials in my signature.

if you play with idle screw when tps is connected, you change how much the aac is open. disconnect the battery for a few minutes and then set idle with tps disconnected.

to see if you have a vacuum leak , plug the hose that supplies air to iacv and air regulator. the hose feeds off the intake before it reaches throttle.

you should also adjust the tps to .4 to .5 volts while it is plugged in. dont bother with resistance test. you should get consult becuase it is more than worth the cost ie $50