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Now she runs, but lumpy

mk2davis

Well-known member
Joined
Mar 1, 2015
Messages
191
Location
Ventura, CA
I may post a short video on YouTube so you all have a better sense of what is happening. As the title states, she runs, but it seems lumpy to me. I set the idle to 900 per vfaq instructions, grounding out the number 10 pin inside the cabin and the timing lead. Also set the timing to 5 degrees by only grounding out the timing lead. Is there something else that needs to adjusted? The motor is a new build. After a couple hundred miles, I'll drain the oil, and then it's off to CA smog.

The old fuel was drained, anda new fuel filter was installed.
 

Eztoril

Well-known member
Joined
Aug 31, 2016
Messages
80
Location
Irvine CA
Did you wait till the cooling fans turned on then off? Setting timing needs to be done at operating temperature. I've only used the grounding connector under the hood to set base timing. Have I been doing it wrong lol?
 

mk2davis

Well-known member
Joined
Mar 1, 2015
Messages
191
Location
Ventura, CA
I did wait for the cooling fans to cycle. And you were right for base timing, grounding the two leads is only for setting idle speed.

As this point, I'm going to take the throttle body apart and look at what disaster awaits. Today she resumed doing what she used to do before I redid a few electrical connections. She starts, idles like poopoo at 500rpm, and then stalls. If you give it gas, rpms bounce up, then slowly go down even if throttle pedal is stationary, and then bounce up once throttle pedal is released. This happens for the first 20ish seconds. Then everything is normal.
 

mk2davis

Well-known member
Joined
Mar 1, 2015
Messages
191
Location
Ventura, CA
Turns out one of the cells was bad on the ISC. I tested pins 1 and 2, 2 and 3, 4 and 5, 5 and 6. 1 and 2 was open, the other 3 had 28-30 ohms. If any one knows of an inexpensive place to find these, I'd appreciate the info. So far in my cursory search, they are about 400 and up.

Now the FIAV... I was dumb and disassembled and then tested it. The depth to the little plunger was:
1.27"in 90 C water
1.46" at room temp
1.44" in 0 C water

Does this seem appropriate, and any tricks to set this in it's range? If I tested before disassembling, an I'd be better off. If I don't get any ideas, I'll close this valve and connect the coolant lines as stock.

It's a process, and I am making progress. So there is that. Finding stuff wrong is better than not. TIA for your help.
 

mk2davis

Well-known member
Joined
Mar 1, 2015
Messages
191
Location
Ventura, CA
I did the FIAV mod, although I haven't pressed on the plug yet. I got a ISC from orielly, so that should be good to go.

Unless someone waves me off, things are going back together tomorrow
 

mk2davis

Well-known member
Joined
Mar 1, 2015
Messages
191
Location
Ventura, CA
Got everything back together, and grounded out the two plugs to set the BISS. Idle was rock solid at 800 rpm. But when I disconnect the grounds, it shoots up to 2k, and eventually settles to about 1600.

Ideas?
 

ktmrider

Well-known member
Joined
Sep 10, 2007
Messages
3,128
Location
Tempe, AZ
The ECU driver circuits are bad. Most likely it burned up the new ISC too.

Lots of info on checking your ECU operation including required component checks and replacements.
 
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