Im helping my son with his 1990 3.1L V6 firebird. We were checking the timing and the Chilton book says to disable EST by jumping AB terminals on diagnostic terminal. Then is says it that doesn'e disable it, disconnect the EST bypass. Well shoot, Id love to, but I don't have any idea where it is. I know where it is on my 91 5.7L TPI motor, but I don't see anything on this one like that. I don't think we are disabling it witht jumper because it shows like 20 deg, and is supposed to be 10 according to the book.

Also, the Distributor holddown bolt appears to be 15mm because my 9/16 distirbutor wrench doesnt fit. Is this possible? Where the heck do I get a 15MM distributor wrench beside making one with a welding machine?

thanks

 

over on the right fender, infront of the blower motor. Brown wire, with stripe. DX it.

Distrib bolt is 15mm, I use a shorty wrench that I got from w-m.

 

for the EST, look for a single tan wire either near the coil or behind the passenger side strut tower.

The hold-down bolt is a 15mm. I use an 1/4" drive exstention, 1/4" to 3/8" drive adapter, and a 3/8" drive universal with a 3/8" drive 15mm socket to get to mine.

 

Thanks a lot guys. by the way, what do you set your timing at, 10 I think is recommended.

 

Yup! 10. There should be a sticker on the underside of the hood with that info. On a lot of cars they are missing, like mine.

 

Yeah there is a sticker all right, but the sticker and apparnely the hood, are from a 5.0 TIP car. I found that out when I went to gap the plugs and it said .035. Later I noticed the 5.0 and found out they are supposed to be .045. The car has apparently had some work done to it

 

Mines at 11deg or so. Should be 10

On 3.1's, the plug is over on the fenderwell.

 

Ignore the Chilton instructions. I followed them to the letter when I first timed my car and later discovered that was the reason for it running so poorly. Where they came up with these instructions I have no idea, but they are wrong. Start the engine, disconnect the EST wire, and set the timing with a timing light clipped to the #1 spark wire. Just remember to reconnect that EST wire when you are done. All the bolts on your engine should be metric.

 

Yes, I found the EST bypass, basically in the same place as my 91 350, it was just hidden beneath the wiring harness. Whats the deal with Chilton and jumping the AB terminal? That didn't do anyhing, and I think I remember hearing that you could damage your engine by running it with the AB jumper in.

Its weird, when we checked the timing the other day it was like 20 deg without the bypass disconnected. We checked it again yesterday, armed with knowledge of the location of the EST bypass and a short 15mm wrench and assortment of 15mm socket, swivel, extensions etc. Well the timing before disconnecting the EST bypass wal not like 12 deg, then disconnected it was like 5 deg.

So we tried to loosen the distributo clamp bolt without succes. I went to the Auto parts store and had them order a metric Distributor wrench. So when it gets in I guess we will adjust the timing. I wonder why there was such a difference from one day to the next. ??? It may have not been idling at the exact same speed, but a difference from 20 to 12 is pretty big. An if the base timing is really 5, then the timing is retarded.

 

WHERE DID YOU FIND A 15MM DISTRIBUTOR WRENCH!!!????

I use a stubby 15mm, myself. fun? No. Also, I got rid of the smog pipe that's in the way of it, as well

Set the timing between 10-12ş. I run mine @ 12ş, myself.

 

http://buy1.snapon.com/catalog/tools...e=snapon-store

I doubt any store stocks the 15mm wrench. He said he had to order one. I can get at it with a socket and a universal on an extension so I'm not going to bother with a wrench. I've had to make tools at work, so this doesn't seem hard in comparison.

 

I ordered on from O Reilly Auto parts. It was a special order and may take a week or so. In the meantinme I borrowed on from a mechanic friend. I noticed its a Snap On, the one piece long ones, worked great.

We set the timing but this intermittent problem came back immiediately after setting the timing. changed the ICM and the losing power problem went away, now it it dying at low rpms sometime??

 

Yep, I use a universal also.

Ratchet + 7 " extension + universal (swivel) + 15mm socket