wont start when its cold
#21
Registered User
When you turn the key to ignition, a red rectanguler light on the dash instrument panel that says "engine" should come on. It let's you know that the ECU and EFI system is getting voltage.
#22
i dont have a red engine light but i do have a orange check engine light that does not come on when it is acting up but when it does work that light does come on with the key in the on position. i went out to try to start it and it would not start but i left the key in the on position for about a half hour and it started right up
#24
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If you look at the circuit diagram above, you'll see that the fuel pump gets its power thru the Circuit Opening Relay. That relay is behind the right kick panel above the computer. The Circuit Opening Relay is turned on when the Fuel Pump Switch inside the Air Flow Meter closes as you crank the engine, and the moving plate inside the AFM opens. Maybe your problem is that under severe cold the plate in the AFM isn't moving. You can test the fuel pump and bypass the AFM switch by using the Check Connector [passenger side fenderwell under hood] to turn on the Circuit Opening Relay using a paper clip. With the ignition On, jumper between the Fp and the +B terminals in the Check Connector with a paper clip. This should turn the fuel pump on and you should hear the fuel flowing in the lines under the hood.
Essentially, trying to start the vehicle or having the engine running (and drawing air through the AFM) should both turn the COR on and activate the fuel pump.
I'm going to check the drawings for an 87 and see if they do in fact match this drawing to a tee. However, functionally, the systems work the same- COR is turned on by cranking and/or by airflow through the AFM.
#30
Registered User
Wait a minute.....the FP and B+ terminals in the box, as Abe describes, is in the diagnostic port as you describe that you've already tried but could not get the fuel pump to work that way. Hmmm.....conundrum.
#32
Registered User
Wait another minute....I got confused. Derf!!
You were saying "directly from the battery terminal". I thought you meant the B+ terminal in the diagnostic box.
Oh, and he did say he tried with the key on at the diagnostic port. He just didn't try directly from the battery to FP port/diagnostic box....which wouldn't require the key.
...sorry. <<<ignore me>>>
You were saying "directly from the battery terminal". I thought you meant the B+ terminal in the diagnostic box.
Oh, and he did say he tried with the key on at the diagnostic port. He just didn't try directly from the battery to FP port/diagnostic box....which wouldn't require the key.
...sorry. <<<ignore me>>>
Last edited by thook; 12-27-2008 at 10:36 PM.
#34
Registered User
/me slaps abe...then slaps self.
/sin slaps us both.
/both drink some Irish cream and go to bed.
/'nighty night......zzzzzzzzzzzzzzz
/sin slaps us both.
/both drink some Irish cream and go to bed.
/'nighty night......zzzzzzzzzzzzzzz
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