New Toy

countrycorey

Trust Me I'm an Engineer
Jan 30, 2010
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the pump will run for a couple seconds when you flip the key to run and then shut off. when the engine is running, the pump runs the whole time. its basically a "prime" when you key on engine off
That is what I thought. Thank you for verifying that James!

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countrycorey

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Jan 30, 2010
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Update

Seems the fuel pump is dieing as it'll start and run at idle, but will not Rev past 1000 rpms without stalling.

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countrycorey

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Jan 30, 2010
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Time for another update.

Got the new fuel pump installed yesterday and was able to drive it around town yesterday afternoon. Also put a new set of lug nuts on it as it was missing a few when I got it.

2 things I noticed while driving it around yesterday afternoon.
1. Seems as if it wont rev past 3000 while driving, didn't really push it though
2. Seems like every time I slow down coming to a stop sign or red-light, when I stop it stumbles and dies. I am able to start it right back up with no issue and continue on

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countrycorey

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View attachment 106121

use a paper clip and go to the ALDL connector (its what the obd1 scan tool would plug into). bend the paper clip into a U and use it to jump A and B together. dont worry, wont throw sparks or kill anything. it will put the computer into self diag mode and flash the check engine to match stored codes. you will get 2 stages of flashes kinda like morris code. it will do a quick blink/s then pause, then a quick blink/s again and pause. The first blink/s is the first digit of the code, second blink/s is the second digit of the code. once it does the first code, it will jump straight to the next numerically higher code and blick for the first and second digit like the first code. if will do a loop of all the codes until you pull the paper clip out. if you want to start over, pull the paper clip and put it back in, it will start at the beginning again. if it does one blink, then blinks twice, that code 12 which means no stored codes.

to clear them, pull the battery and let it sit for15-30 sec. it should clear the codes.
Time for another update. Was able to scan the codes causing the CEL to illuminate and these are the three that came up.

15 - Coolant temp sensor or circuit fault (signal voltage high)

34 - MAP sensor voltage is low during ignition on

54 - Fuel pump circuit fault or mixture control solenoid fault or ECM fault /EGR solenoid #2 fault

Going to disconnect the battery a d see what clears. Fuel pump/relay code may be due to me troubleshooting the fuel pump
Any suggestions?
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Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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lets see what comes back. coolant temp sensor and map issue may be the reason it falls on its face over 3k rpm
 

countrycorey

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lets see what comes back. coolant temp sensor and map issue may be the reason it falls on its face over 3k rpm
The coolant temp sensor or circuit fault (Code 15) and the MAP sensor signal voltage is low at ignition on (Code 34).

Looks like I need to order a new map sensor and Coolant sensor.
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Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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verify the voltage first. see what the map sensor is seeing. it should have a dedicated 5v to the sensor, a ground and a sensor wire. see if its getting 5v. if not, start back tracing. may have corrsion build up somewhere. coolant sensor may just need replacing, they are cheap enough to jsut throw on at it and see.
 

countrycorey

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lets see what comes back. coolant temp sensor and map issue may be the reason it falls on its face over 3k rpm
Also found this on while.looking at the MAP sensor and the EGR. Is there supposed to be something plugged in there?
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countrycorey

Trust Me I'm an Engineer
Jan 30, 2010
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verify the voltage first. see what the map sensor is seeing. it should have a dedicated 5v to the sensor, a ground and a sensor wire. see if its getting 5v. if not, start back tracing. may have corrsion build up somewhere. coolant sensor may just need replacing, they are cheap enough to jsut throw on at it and see.
I'll pull the connector in the morning and see what I can find. It should have 5v with the key in run, correct?

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countrycorey

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First thing I found was the connectors for both sensors (Coolant and MAP) have broken retaining clips.

MAP sensor has 5V supply with the key on and >0.3V on the other two pins when connected to ground. Gonna replace both sensors and see if I can get replacement connectors for the wiring harness.

Also got the windshield wipers working!! Still can't get the rear hatch open, need a second person to help.
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countrycorey

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Just for shits and grins, my plans are to eventually swap out the engine and/or EFI system. Main two options I have been considering are:

1. 383 SBC with an aftermarket EFI system (Sniper or Pro-Flo)
2. LS swap (not sure what engine or EFI setup)

Main issue I am running into is the failing connectors and unknown wiring issue/repair quality.


Also would like to do either an SAS or IFS Lift, but those are off the table until the engine is running reliably or EFI swap is done.
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countrycorey

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Next update:

Been driving it on my Fridays and have notices once it warms up that it didn't stall this past Friday when driving it around. I ordered a new Coolant sensor and MAP sensor to replace the old ones. The coolant sensor was broken off leaving only the pins exposed, and it had the wrong connector plugged into it. Replaced the MAP sensor and connector and then disconnected the battery to reset any codes.

Started the truck and idled much better instantly and no stumbling when stabbing the throttle, and NO CEL!!!!

Also put husky liners up front and in the cargo area!


Anyone know where a spare tire mount for a two door tahoe or yukon would be laying around is?
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Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
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LS swap with a carb intake and throttle body on top, then choose an efi system that will run coil on plug igniton (cant run a distributor on a LS).

otherwise id say to just put heads cam intake (absolute most you can afford) on, a throttle body efi system and go have fun. you will be limited by the NV3500 and clutch anyhow.
 

countrycorey

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LS swap with a carb intake and throttle body on top, then choose an efi system that will run coil on plug igniton (cant run a distributor on a LS).

otherwise id say to just put heads cam intake (absolute most you can afford) on, a throttle body efi system and go have fun. you will be limited by the NV3500 and clutch anyhow.
You need to swap in an lq4 and have some fun with that thing!
5.3 or 6.0 and maybe this? Or ive always wanted a 383
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