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Ignition Timing


jor

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Posted

87 5.7L TBI Suburban 4WD

Well, this is my first post to this board. I usually work on my Ford trucks but I recently picked up an 87 Suburban. I am really unfamiliar with these engines and I am looking for some very basic information. I did a compression check on it and all the cylinders are between 160 & 170. Now I want to check the ignition timing but I'll be darned if I can find the EST bypass wire. I have the shop manual and it indicates that

 

On the V6 and V8 engines, the system will go into Bypass Mode by disconnecting the timing connector. This is a single wire sealed connector that has a tan with black stripe lead. On the 4.3L and V8 engine, this connector breaks out of the engine wiring harness conduit adjacent to the distributor.

 

I sure can't find that &*&@! wire!!! Here's a few photos I took of the area in which I am looking. BTW, I went through the FAQs (pretty impressive!) and did some searching but apparently, this question is so fundamental that no one has ever asked! Anyhow, I sure could use some help on this. Thanks.

jor

 

http://i102.photobucket.com/albums/m105/jo...omponents-6.jpg

 

http://i102.photobucket.com/albums/m105/jo...omponents-5.jpg

 

http://i102.photobucket.com/albums/m105/jo...omponents-7.jpg

Posted
I'm going from memory. I think it's on the passenger side firewall by the relays under the hood. I think there is a cover you have to remove to get to it.

Hmmmm... the shop manual says that's where it is on the 2.8L engine but I'll take a look tomorrow where you suggest. Thanks.

jor

Posted
I'm going from memory. I think it's on the passenger side firewall by the relays under the hood. I think there is a cover you have to remove to get to it.

Hmmmm... the shop manual says that's where it is on the 2.8L engine but I'll take a look tomorrow where you suggest. Thanks.

jor

 

 

Turned out it was on the driver's side, just under the brake booster. It was taped up under the loom so I missed it. Anyhow, I got it timed now so that's a step in the right direction.

jor

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