Iginition Timing 89 Corvette

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Apr 22, 2007 | 09:50 AM

berry72

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Cruising

Joined: Apr 2007

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From: Nashville TN

Iginition Timing 89 Corvette

I have been trying to locate the plug for the EST. Under the hood tells me that the wire is a tan closed single wire with a black strip. I have searched high and low and still no plug?? Any help is much appreciated!

Also - one other issue / I am trying to run down a vacuum schematic - same issue under hood doesn't show the full picture. The vacuum hose running from the EGR selnoid goes directly to the EGR valve which makes sense to me but should same hose also go directly to the fuel pressure regulator? There are 2 vacuum hook ups on the passenger side of the plenum - one goes to HVAC and the other to the fuel pressure regulator - not sure if that is correct? Does anyone out there have 89 corvette that cold look at and give the answeres I need?

Apr 22, 2007 | 10:43 AM

cv67

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Joined: Oct 2004

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From: altered state

St. Jude Donor '05

EST wire-look around the distributor/master cylinder area near the firewall. May have to dig through the harness to find it though.

Apr 22, 2007 | 12:43 PM

vinnies87

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Joined: Aug 2003

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From: Magnolia Mississippi

St. Jude '03-'04-'05-'06-'07

EST: Check in the wire bundle/wrap around where cuininartvette said, sometimes its in the wire bundle.

Vacume: Use the search function and include archives in the search...

Apr 22, 2007 | 04:05 PM

65Z01

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From: SE NY

Cruise-In II Veteran

The vac line from the EGR sol goes to a T and into the fitting under the TB.

The AFPR connects directly to the vac fitting on the RH side of the plenum rear. On earlier C4s there might be a T going to the AIR diverter valves.

Apr 22, 2007 | 07:53 PM

Slalom4me

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Joined: Jan 2002

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From: Edmonton AB

You've received several posts with help for location the EST connector

Here are photos 86Pacer contributed in 'whats the EST and where is it'

Tan wire w/ Black stripe

Apr 23, 2007 | 04:45 PM

berry72

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Cruising

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From: Nashville TN

I found it and I've got the timing adjusted. The car runs pretty good but surges when idling and also when driving along and not touching the gas the engine will idle up and then back down. I believe I have a vacuum hose hooked up wrong. I followed the diagram under the hood but something still seems to be causing the car to backfire every once in a while - not bad but nevertheless something isn't right. Any suggestions?

Thanks to all for your help!

Apr 24, 2007 | 10:03 AM

berry72

Thread Starter

Cruising

Joined: Apr 2007

Posts: 13

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From: Nashville TN

I got it - thanks to all...!!!

I found the vacuum leak by blowing smoke into the intake which was an idea given to me on another thread I had open!

This place is great! Thanks to all...!!!!!

Apr 24, 2007 | 10:40 AM

sami85L98

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Joined: Apr 2005

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From: Scarborough ONTARIO

Cool, glad worked out for ya, smoke detector machines are the best to use for detectin vacum leaks, i did at my mech place, it was a such tiny spot i would have never detect with water or any spray kind. No enjoy.