RPM drop very low after/during startup
03-04-2014, 08:46 AM
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RPM drop very low after/during startup
When I start my 88 runner 22re, the RPM are fine when the engine first begins to run (for the first half second or so).
Then the RPM immediately drop very low (~200 to 250), the engine sounds like someone starting on a weak battery but faster, it struggles to keep going, then it dies.
If I put my foot slightly into the pedal before turning the key in anticipation of the drop, everything seems to be fine except for the occasional over rev.
Has anyone experienced this?
Any thoughts on where to begin looking would be appreciated.
Then the RPM immediately drop very low (~200 to 250), the engine sounds like someone starting on a weak battery but faster, it struggles to keep going, then it dies.
If I put my foot slightly into the pedal before turning the key in anticipation of the drop, everything seems to be fine except for the occasional over rev.
Has anyone experienced this?
Any thoughts on where to begin looking would be appreciated.
03-04-2014, 11:02 PM
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I pulled the IAC valve (cold assist bi-metal thingamabob) and cleaned it well. I soaked the throttle body with TB cleaner. Now I intermittently get the high-low, high-low surging RPM in addition to the drop immediately after ignition.
I'll clean the EGR valve and check the cold start injector next.
I'll have to remove the throttle body to check hose stem (that gets clogged) next to the thermostat, and I don't think I want to do that (no skills).
Any other ideas? Bad TPS? Bad temperature sender?
I'll clean the EGR valve and check the cold start injector next.
I'll have to remove the throttle body to check hose stem (that gets clogged) next to the thermostat, and I don't think I want to do that (no skills).
Any other ideas? Bad TPS? Bad temperature sender?
03-08-2014, 01:58 PM
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Ok, so I’ve ohmed, cleaned, and otherwise checked:
cold start bimetal air thingamajig,
cold start timing switch,
cold start injector,
water temperature sender,
throttle position sensor,
massair flow sensor,
dashpot stop position,
blasted throttle body with cleaner,
hosed down vacuum hoses with starting fluid and carb cleaner to listen for change,
plugged emission gas recirculator to test if stuck open,
jumped B+ and FP to bypass air flow sensor and open circuit relay.
My runner is starting better, but the RPM still drop (to ~250) immediately after ignition, which leads to a “weak battery” sounding struggle to remain running/complete starting.
She fires right up if I put a little petal into it, and she runs like a sewing machine after barely warming up.
Next, I’m going to do rotor button, distributor cap, plugs, wires, and timing.
Any suggestions?
cold start bimetal air thingamajig,
cold start timing switch,
cold start injector,
water temperature sender,
throttle position sensor,
massair flow sensor,
dashpot stop position,
blasted throttle body with cleaner,
hosed down vacuum hoses with starting fluid and carb cleaner to listen for change,
plugged emission gas recirculator to test if stuck open,
jumped B+ and FP to bypass air flow sensor and open circuit relay.
My runner is starting better, but the RPM still drop (to ~250) immediately after ignition, which leads to a “weak battery” sounding struggle to remain running/complete starting.
She fires right up if I put a little petal into it, and she runs like a sewing machine after barely warming up.
Next, I’m going to do rotor button, distributor cap, plugs, wires, and timing.
Any suggestions?
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