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Icebird
07-18-2014, 12:18 PM
Hi there
There is one vaccum port that is bothering me. It is blocked now and my car the hicups when its under load. This port is behind the valvecover and beside the tranny dipstick. I am going to try to take photo of this over the weekend.

PAlli

racecougar
07-18-2014, 07:48 PM
What exactly is the port doing to bother you?

Icebird
07-23-2014, 10:29 AM
Hi there
Its not plugged to anything and has bolt in the end so I was thinking where it goose ? Anotherthing My SC is always misfire under load and now I see the tach is sometime not working or falls down when this happens ? what is that ????????????

PAlli

KMT
07-23-2014, 10:32 AM
Another thing My SC is always misfire under load and now I see the tach is sometime not working or falls down when this happens ?

Sounds like it needs a new cam sensor. Have you run the codes yet?

Les Borda
07-23-2014, 11:11 AM
http://www.sccoa.com/forums/showthread.php?89550-vacuum-line-between-plenums&highlight=block+off+vacuum+line

Is it possibly this tube shown in this link?

KMT provided me with this.

S_Mazza
07-23-2014, 11:25 AM
http://www.sccoa.com/forums/showthre...ff+vacuum+line

Is it possibly this tube shown in this link?

KMT provided me with this.

The link isn't working.

To the OP - I am wondering if it's your PCV system line? Or possibly the charcoal canister line? Can you get a picture?

Les Borda
07-23-2014, 11:49 AM
Thanks the link works now

Icebird
07-30-2014, 01:29 PM
Hi there
I am waiting for my friend to come back from vacation so I can go and get the other sensor that I have. So no update here yet :rolleyes:

Palli

Icebird
07-31-2014, 04:48 AM
Ok
Here it is boys.I change the cam sensor last night and tach stay at his place so thats ok but there is still some hick ups in it under load ? I did not disconect the battery ? Do I need to do that to zero the computer or do I just go straight to change the spark plugs ( they are new ) . The ground straps are new and I put two extra there also.

PAlli

S_Mazza
07-31-2014, 10:28 AM
Ok
Here it is boys.I change the cam sensor last night and tach stay at his place so thats ok but there is still some hick ups in it under load ? I did not disconect the battery ? Do I need to do that to zero the computer or do I just go straight to change the spark plugs ( they are new ) . The ground straps are new and I put two extra there also.

PAlli

If it misfires only under heavy load, that sounds like it's probably a problem with the secondary ignition. To me, that sort of problem would show up as a heavy jerk when trying to accelerate under boost, but working fine at cruise.

It could be excessive plug gap, or a slightly cracked insulator, or a chafed or melted plug wire, or even a loose plug boot. I would check the plug boots first!

WhiteThunder
07-31-2014, 02:22 PM
If it misfires only under heavy load, that sounds like it's probably a problem with the secondary ignition. To me, that sort of problem would show up as a heavy jerk when trying to accelerate under boost, but working fine at cruise.

It could be excessive plug gap, or a slightly cracked insulator, or a chafed or melted plug wire, or even a loose plug boot. I would check the plug boots first!

We had the same problem with our 5-speed SC - breaking up under heavy load like about 4,000 rpm and higher. Looked in the receipt book and saw the plugs were last changed in 2005 and wires in 2007.

Put in a set of Autolite 103s gapped at 35 and a new set of Taylor wires. Problem solved. Now she's hitting 6,000 rpm (with 519 lift cam and 17 - 18 lbs of boost) with no problem.

The Autolites we pulled out (2455s - don't recall why those plugs were in there). The gap was 50 to 60 on those puppies.

Eddie Donato
'90 5-speed highly modified
'90 automatic stock, except for double intercooler

Icebird
08-01-2014, 06:31 AM
Thanks guys
I see if I can pull the plugs this weekend if I can find the right ones here in Iceland if not I have to order them. This misfire are around 1200 and up.

Palli