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89 Kick - Cold start gas pedal feathering annoyance
#1
89 Kick, 8V, 4x4 , AT, 195K, Cat removed by PO

- Getting immediate 12V at Dashpot VSV upon start, no matter how cold or warm.. Dashpot gets immediate vacuum at start.. VSV tested manually and works fine with 12V applied and removed.  Clicks heard, and air test thru filter works perfect.
- ECT Sensor replaced and tested. ECT tests good
- IAC Wax pellet is bad.. 1/2 OD host routed with no vacuum leaks from IAC intake to inside dashboard to manually switch IAC on/off.. I use a golf tee to plug the hose once warm and idle can drop to 850.  Works well for me.
- When starting cold, IAC gets air to intake from hose , but must feather gas pedal to add air to start.. Then feather for 15 seconds till IAC can work alone with air coming from manually controlled hose to intake from inside car. Franken IAC replacing thermal wax valve  
- If I pull hose at VSV to disable dashpot vacuum, and add air to intake thru hose, I still must feather gas to start when cold
- If I pull VSV hose to dashpot when car is hot (remove vacuum), Idle goes to 2500ish so dashpot works as it should.

Car idles 850 hot, 1100 with lights on (ISC controlled)..  
Cart starts fine hot with no feathering of gas pedal.. Life is good once hot.

Any ideas why dashpot may be getting 12V at all times car is started?   ECU maybe?  I have not checked Caps yet, unknown if PO changed caps, but could this cause this issue.. No other issues ECU related 
Any ideas why the need to feather gas still if (Intake is getting air from hose and dashpot vacuum is manually disabled?

Thanks all..  Enjoying my Kick in Arizona
1989 Sidekick JLX
8V 1.6L
2 Dr Convertible
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#2
DP can be like 3 seconds hot engine to 30 or tad more super cold. but the ECT must work or the ECU has no idea at all what to do.
ECT at 300ohms resistor at hot engine 180f, stop engine  pull plug to ECT (has locks) and is  measured 300ohms,. (about) check cold to against my ECT table.
IAC dead is huge pain.
yes IAC provides allmost all air for cold starts ( and TV a tiny bit) when it dies IAC stuck up cold starts scream if stock closed floods unless driver right foot adds some.

the DP is mostly for burning up all that pooled liquid fuel on super cold starts. under the TB plenum box (small) it can be like lake of fuel and nasty smog as result.
but is also part of cold start up air
the ECU sadly is hard coded in memory ECU for assumed, air flows, at cold start then when map wakes up gets smarter (tons). at idle and up to WOT

so the air flow is DP +IAC +  TV small leak = idle cold air start. DP is open cranking, he delay is after engine idle rpm shows running.

The IAC is thermal no ECU controls but is done by proxy it uses ECT to model The IAC,   It knows air flow in IAC at all temps from Icelandic temps to to 150f and IAC .
the ISC wakes up (electr) at 150f adding more air.

ECU  knows DP (performance) as it runs that, fully. at all times (VSV)
it is not easy to do this, but I sure would,  using a valve or a set of orifices/ valves (solenoid) I can choose.
1-_ no air hot.
2:  not cold air.
3: fridge air. orifice.

or buy a generic IAC and run it off an Arduino AVR and program it to ECT temps. (AVR connected to ECT) summit racing dot com has generic IAC. for race cars.

I do feel your pain here, it is not easy to outsmart any ECU but not insurmountable.
cheers too you !
http://www.fixkick.com
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