89 2.9 Timing

[saling4]

I am sure this has been asked 4 zillion times, but here it is again. On a 89 2.9 is the timing with the SPOUT removed 10* ATDC or 10*BTDC? I saw in a faq here that 10*ATDC, but my emissions sticker says 10*BTDC with SPOUT removed. At 10*ATDC (SPOUT removed) it is about 12*BTDC with it plugged in.

Just to be sure BTDC is to the right of TDC as you look from the front of the truck, correct?

Confused in Vegas.

 

[low_five]

btdc

is there even a mark on the pulley for ATDC?

 

[saling4]

Heck now I have to look again. It could be I looked at the 10* BTDC and the distance to where it is now is about the same except ATDC. This gets stranger and stranger, but I will set it to 10* btdc with SPOUT out and see what happens.

 

[saling4]

Adjusted timing

I adjusted timing to 10* BTDC with SPOUT removed. When SPOUT is back in it is at about 20*. Does this sound about right? I am currently tracking down a vacuum leak (I think) The timing is changing between 20-27* and I know that can't be right. IDeas?

 

[low_five]

that sounds about right.

 

[saling4]

Thanks low five. Now to figure out that pesky surging. I did find out why it all of a sudden got loud as heck. Big hole in the muffler. Now to find something to put back on for that problem.

 

[saling4]

I read the codes and they are 29 and 41. VSS error and HEGO sensor indicates lean. WHatever a HEGO sensor is.

 

[saling4]

These appear to be memory codes and not hard codes. Is the HEGO sensor the 02 sensor?

 

[IMenriched]

These appear to be memory codes and not hard codes. Is the HEGO sensor the 02 sensor?

Yep

 

[doorgunner]

The Tech Library will tell you how to test the HEGO(0/2 sensor & wiring). Fix the vaccum leak & the 0/2 sensor might start acting right by itself. My VSS had xmsn fluid in the electrical connector--I cleaned everything good with elec. contac spray and everything is good now---if it fills up with xmsn fluid again, I'll replace the VSS.

 

[saling4]

Thanks guys. I will get to the bottom of this rough idle if it kills me (or my wife kills me).

 

[JOKER86]

I read the codes and they are 29 and 41. VSS error and HEGO sensor indicates lean. WHatever a HEGO sensor is.

its a heated exhaust gas oxygen sensor

if u have a vaccum leak, that might be causeing the problem

 

[turbo cat]

Surging at idle is a sign of a very lean idle due to a fuel problem or vaccum leak ussually