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General Site Info => General Discussion => Topic started by: Kevin108 on June 16, 2002, 10:50:00 am

Title: How do I get codes from my 87?
Post by: Kevin108 on June 16, 2002, 10:50:00 am: Intermittently on long trips my Service Engine Soon light comes on. When I stop for for a couple minutes, turn the truck off, and start the truck again it's never there. It's only happened twice now but I'm curious nonetheless.
87 Silverado 4x4 Longbed Pickup
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Title: Re: How do I get codes from my 87?
Post by: VileZambonie on June 16, 2002, 08:53:00 pm: It's probably the infamous EST error, but just stick a paper clip in the a+b terminals in the ALDL connector and turn the Key on. Count the flashes. ex. flash-flash-pause-flash = code 21
Title: Re: How do I get codes from my 87?
Post by: Kevin108 on June 16, 2002, 10:30:00 pm: Dell, can you tell me more about this? Never had anything with a computer before. Played around with an 89 F-150 so I know how the flashes work and all but is there like a webpage I can reference codes from?

*edit*

I harvested these codes from another board:

heres a GM code list:
13 Oxygen sensor voltage stays between 0.35 and 0.55 volts for 60 seconds.
14 Coolant temperature sensor signal indicates a temperature of over 275° F for 2 seconds.
15 Coolant temperature sensor signal indicates a temperature colder than -27° F for 30 seconds after the engine has been running for at least 30 seconds.
21 TPS voltage was above 2.5 volts for 8 seconds when the MAP sensor signal showed manifold vacuum to be 15 pounds or more.
22 TPS voltage was under 0.2 volts for 2 seconds when the engine was running.
23 Inlet air temperature sensor signal showed an air temperature below -22° F after the engine has been running for 5 minutes.
24 Vehicle Speed Sensor (VSS) Circuit .
25 Inlet air temperature sensor signal showed an air temperature over 302° F after the engine has been running for 5 minutes.
32 EGR open command did not change MAP sensor signal. Normal EGR flow should cause slight decrease in manifold vacuum which would change MAP sensor signal.
33 MAP sensor signal voltage was too high (low vacuum) for 5 seconds when throttle opening was under 4%.
34 MAP sensor signal voltage was too low (high vacuum) when engine speed was under 1200 RPM or the engine speed was over 1200 RPM with a throttle position angle above 21%.
35 Idle Air Control (IAC) System .
42 The EST signal did not change when the ECM applied bypass voltage to the ignition module.
43 The ECM did not detect a knock signal during near wide open throttle operation with coolant temperature above 194° F or the knock signal was present for 5 seconds or more during normal engine operation.
Electronic Spark Control (ESC) Circuit .
44 Oxygen sensor voltage was under 0.2 volts for 50 seconds of closed loop operation.
(Lean Exhaust Indicated)
45 Oxygen sensor voltage was over 0.7 volts for 30 seconds of closed loop operation with a throttle angle between 2% and 20%.(Rich Exhaust Indicated)
51 PROM error. (MEM-CAL)
52 CALPAK error.Fuel CALPAK Missing .
53 System Over Voltage .
54 Fuel pump voltage was not present at fuel pump sense line for 2 seconds after the ECM has sent the fuel pump on command.(Low Voltage)
55 ECM error. Replace ECM.Faulty ECM
this is not a giant code to worry about. faulty EGR, EGR port
restriction. basically in a nutshell, the computer commanded the EGR
to open and the test failed as the MAP and/or O2 didnt sense any
change when the command to open EGR was given.
airdeano
87 Silverado 4x4 Longbed Pickup
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Edited by: Kevin108 at: 6/17/02 5:30:41 pm
Title: Re: How do I get codes from my 87?
Post by: Kevin108 on June 17, 2002, 12:52:00 pm: And I got the codes 12 and 32 just now...
87 Silverado 4x4 Longbed Pickup
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Title: Re: How do I get codes from my 87?
Post by: VileZambonie on June 17, 2002, 09:57:00 pm: 12= OK

32= EGR malfunction.

Check the EGR Valve, make sure the vacuum hose is hooked up. Press up on the bottom of the diaphram with the engine at idle. It should stall the engine or at least make it run like crap. If that's ok and and there is manifold vac to one side of the EGR solenoid and none on the other side than that is ok too. If all of this checks out ok, than the EGR Solenoid is probably not opening allowing vac to the EGR Valve when commanded. Check all of that and let me know how you make out.
Title: Re: How do I get codes from my 87?
Post by: Kevin108 on June 17, 2002, 11:04:00 pm: I got Dad to dig around in and he pulled out a GM engine book that had all the codes in it. I'll play around with the EGR stuff this week. According to the book there's a few possibilities that 32 could be.
87 Silverado 4x4 Longbed Pickup
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Title: Re: How do I get codes from my 87?
Post by: VileZambonie on June 20, 2002, 11:21:00 pm: 32 is EGR malfunction.
Title: 87 codes
Post by: lumpyokc on June 25, 2002, 11:10:00 am: its from your flowmaster mufflers they do not have enough back pressure i know thjis because i have a freind who has a garage my 87 did this and he scanned it and said it was from high performance exhaust
Title: Re: 87 codes
Post by: 83CHEVY on June 25, 2002, 03:14:00 pm: If I remember right, that code indicates low blinker fluid.

Mike
Title: Re: 87 codes
Post by: Kevin108 on June 25, 2002, 10:17:00 pm: Oops...delete this.

Read below:
87 Silverado 4x4 Longbed Pickup
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Edited by: Kevin108 at: 6/26/02 3:23:01 am
Title: Re: 87 codes
Post by: Kevin108 on June 25, 2002, 10:22:00 pm: I've got plenty of blinker fluid... Since it's poor backpressure then maybe my muffler bearings are bad.
87 Silverado 4x4 Longbed Pickup
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Title: Re: 87 codes
Post by: 83CHEVY on June 26, 2002, 09:38:00 am: Could be, but you'll find out since the muffler bearing carrier is right in the way of the blinker fluid reservoir. So they would have to come out anyway

Mike
Title: Re: 87 codes
Post by: Kevin108 on June 26, 2002, 11:41:00 pm: So when did I get Flowmasters? Last time I looked, all I had was a cat and straight pipes...
87 Silverado 4x4 Longbed Pickup
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Title: Re: 87 codes
Post by: 83CHEVY on June 27, 2002, 09:21:00 am: Maybe they fell off due to a muffler bearing failure?

Mike