High Idle Advice - Delete Decel Valve?
#16
Burning Brakes
Thread Starter
Mark,
I have a stock, never molested, owned from new 81 Auto down here in Rancho Bernardo - I have all the test gear and 30 years of wrenching on the old guys to figure out ( 90% certain) what your problem is.
If you feel like taking a drive and coming on over, PM me if you are interested.
I have a stock, never molested, owned from new 81 Auto down here in Rancho Bernardo - I have all the test gear and 30 years of wrenching on the old guys to figure out ( 90% certain) what your problem is.
If you feel like taking a drive and coming on over, PM me if you are interested.
#17
Burning Brakes
Thread Starter
For the past month I have spent some weekends working on the 928. I have found a few vacuum leaks and the decel valve was just barely hanging on. Idle is more stable now and I feel rather good about doing this myself. Also this month I needed to replace the return power steering hose since it was not routed correctly and was brushing against another hose and wore a hole in it.
Yesterday found 2 gas leaks, 1 at the fuel pump (need new copper washers) and one above but need to drop the tank for that one. I am getting a huge education working on this car. I wanted to post my progress and feelings thus far. The 928 is everything, everyone says it is.........including the maintenance and I understand what a project car is now. I am as happy as a pig in slop as the saying goes. I am still a newbie but I am learning. Thanks for all the responses to my posts.
Yesterday found 2 gas leaks, 1 at the fuel pump (need new copper washers) and one above but need to drop the tank for that one. I am getting a huge education working on this car. I wanted to post my progress and feelings thus far. The 928 is everything, everyone says it is.........including the maintenance and I understand what a project car is now. I am as happy as a pig in slop as the saying goes. I am still a newbie but I am learning. Thanks for all the responses to my posts.
#18
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The fuel leak on top of the tank may be around the level sender. You can access it from inside the car. Lift the carpet locate the plastic disc and pop it up. You are then looking at the sender and fuel return line. The large outer nut unscrews. Also note if anyone has mounted speakers or amps to the deck they easily may have drilled holes in the plastic tank....
#19
Burning Brakes
Thread Starter
Might be better left installed on a street driven CIS car. The 'injectors' are just spring loaded check valves. High vacuum will pull fuel through them. (L-Jet has proper electric solenoid valves. )
The factory deleted the limiter on '83-'84 auto L-Jet engines. (5-speeds may want to raise the idle by 50 rpm or so to forestall stalling.)
Factory caps might help with a visual inspection.
999 703 171 40 cap 14x15
999 703 172 40 cap 18x15
'84 auto:
The factory deleted the limiter on '83-'84 auto L-Jet engines. (5-speeds may want to raise the idle by 50 rpm or so to forestall stalling.)
Factory caps might help with a visual inspection.
999 703 171 40 cap 14x15
999 703 172 40 cap 18x15
'84 auto:
#21
Burning Brakes
Thread Starter
The fuel leak on top of the tank may be around the level sender. You can access it from inside the car. Lift the carpet locate the plastic disc and pop it up. You are then looking at the sender and fuel return line. The large outer nut unscrews. Also note if anyone has mounted speakers or amps to the deck they easily may have drilled holes in the plastic tank....
#22
Burning Brakes
Thread Starter
Well then, that is what I am going to do. Thanks Randy. 928 intl does not carry the plugs but Pelican Parts does so ordering them tonight. I was a little hesitant to do this but this cinches it for me.
#23
Burning Brakes
Thread Starter
The fuel leak on top of the tank may be around the level sender. You can access it from inside the car. Lift the carpet locate the plastic disc and pop it up. You are then looking at the sender and fuel return line. The large outer nut unscrews. Also note if anyone has mounted speakers or amps to the deck they easily may have drilled holes in the plastic tank....
#24
Administrator - "Tyson"
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General rule of thumb, if you don't know if the guides / seals have been replaced in your car, they are probably original.
The valve is only supposed to be open at very high vacuum conditions under decel. At 16-17 inHg the valve closes.
It's currently disabled on my 81 (with EuroS brains) and the "glass-pack" pick-up truck deceleration pop is getting annoying. Unlike with L-Jet, I cannot simply remove the idle switch unless I feel like changing both LH & EZK maps to control idle without the idle maps in play. Not a big deal but I fail to see the advantage.
#25
Burning Brakes
Thread Starter
I was in there already fixing coolant leaks in the back and decided to give it a try.
I hope this works out okay. The parts guru at oops, it was Pelican Parts and that guru said it was okay to delete decel since he also did it.
Last edited by SanDiego928; 09-22-2011 at 01:16 AM. Reason: mistakenly said wrote wrong supplier
#27
Burning Brakes
Thread Starter