My mileage sucks!

[Buicksx3]

Brent,

You might try giving Tim Lee at Don Lee Automotive in Rancho Cucamonga a call RE: a gear swap or an 8.5" rear end. Tim swapped a GN drivetrain into his '65 Skylark that runs 10.70s so he has a solid handle on these Turbo Regals. Plus, he's in your neck of the woods on Foothill Blvd., just east of Archibald.

Don Lee Automotive
9793 Foothill Blvd.
Rancho Cucamonga, CA 91730
(909) 989-1573

Hope this helps,

Morgan
'87 GN; high 10's...finally.

 

[wiked87gn]

hey brent the aftermarket chip you got in there came from Lou C in lake forest it is a good chip and it was made from 160* stat, with 22* of timing he makes his chips a bit on the rich side but they work well, normally you would want to have a 17*/18 * timing street chip for 91 octane, but since your getting alky I would keep the extender that came with the sale of the car, dont spend any more money on other chips trust me I have been there done that and have ended up with at least 5 different chips to pick from and become useless overtime.. just be patience and things will come tegether nicely..

 

[VadersV6]

yeah, I wasnt planning on buying any more chips. I just wanted to know if the stock chip might be a little safer in the meantime, given our crappy gas.
I fixed the speedo. I just popped the dash section above speedo, pulled the speedo bezel, and removed the speedo assembly. I pulled the whole speedo cable out and greased the hell out of it. When I started driving, it was still making noise, but after about 1/2 mile, the noise went away and it now works like a champ. Unfortunately, the prior owner didnt change the speedo gear to compensate for the gears, so its reading high. I also noticed while I was in there, that the brake sensor was way out of adjustment, and there is no locking nut on there to keep it from drifting back. I readjusted it, but its definetely going to move again.

 

[VadersV6]

Originally posted by turbo2nr
Don't forget the fans cut off at around 35mph! Speed cut off is also removed.

What do you mean? If you run a TCC switch, or jump the top left and right pins on the ALDL connector, these other problems pop up? Please elaborate. Also, what is the speed cut off?
Bye the way, it seems I was full of **** about the mileage improving dramatically. I have a very unstable fuel level gauge. It'll stick in one position and make it seem like I barely used any gas. Then after driving it again, the needle plummets and shows my true fuel level. Its kind of scary not knowing how much gas I have left in the tank!

 

[pacecarta]

the tank reading being incorrect was in the back of my mind , not a good judge for MPG calculating .best way to determine fuel is fill to it gas pump kicks off ( dont top off the tank ) note odometer reading drive out about half tank and refill noting how much went in till pump kicks off and mileage at fill up .

411s would increase your cruise rpm but if the trans hasspeedo gears for the 3.42 rear your speedo would read less mph as well as less miles traveled on the odometer.

the brake switch doesnt have a locknut just a push in retainer clip , if the switch is not holding tight the plastic grooves are probably wornout and it should be replaced
if it is infact the brakelight combo switch it also contolls the lockup and it will not engage if its loose , if your brake lights are on all the time that could be a big safety problem
if its the other switch its for cruise control and no big deal unless you use cruise

 

[BlackBandit]

Originally posted by pacecarta
411s would increase your cruise rpm but if the trans hasspeedo gears for the 3.42 rear your speedo would read less mph as well as less miles traveled on the odometer.

Are you sure about this? It seems like if you change to a lower (numerically higher) gear without changing the speedo gear your speedo would read as if you where going faster than you actually are and it would log more miles on the clock.

 

[VadersV6]

Originally posted by pacecarta
the tank reading being incorrect was in the back of my mind , not a good judge for MPG calculating .best way to determine fuel is fill to it gas pump kicks off ( dont top off the tank ) note odometer reading drive out about half tank and refill noting how much went in till pump kicks off and mileage at fill up .

411s would increase your cruise rpm but if the trans hasspeedo gears for the 3.42 rear your speedo would read less mph as well as less miles traveled on the odometer.

the brake switch doesnt have a locknut just a push in retainer clip , if the switch is not holding tight the plastic grooves are probably wornout and it should be replaced
if it is infact the brakelight combo switch it also contolls the lockup and it will not engage if its loose , if your brake lights are on all the time that could be a big safety problem
if its the other switch its for cruise control and no big deal unless you use cruise

Well, I do know in fact that the rpms would be higher by switching to a numerically higher gear, if the speedo gear is for a 3.42. Ive installed gears in all my hot rods and this has always been the case. In this case, it will be reading about 15mph higher than normal. In my cobra, my speedo went up 20mph, going from a 3.27, to a 4.10 gear. It was almost 40 higher with the 4.56's. So which switch is which? Im referring to the one that goes right on the brake pedal arm. I see no other switch anywhere.

 

[pacecarta]

you are right , dont know what i was thinking , it should read 17% above actual speed , 50 mph should read about 58 (hope i got it right this time) on speedo which would engage lockup sooner

 

[pacecarta]

you wont have another switch if you dont have cruise

are your brake lights on ,

 

[Ttype6]

Re: milage sucks

Originally posted by BlackBandit
Are you sure about this? It seems like if you change to a lower (numerically higher) gear without changing the speedo gear your speedo would read as if you where going faster than you actually are and it would log more miles on the clock.

Correct.

 

[VadersV6]

Well, I do have cruise control, and my brake lights only come on if I hit the pedal. Is this second switch normally located right next to the brake switch?

 

[pacecarta]

they are inline one above the other , if you depress the pedal it should activate both switches

 

[VadersV6]

I wonder why the switch is not there.

 

[wiked87gn]

the stock chip would not be better than the one u got, 1st it will make the fan come on at 194 instead of 168 second the stock chip also has 22 degress of timing so just leave the one u got there until you place the extender in there with the new injectors..

 

[VadersV6]

Update- Associated with my mileage problem, was my car idling terrible. I had to turn the screw up till I was at 1000rpm. Anything below that and the engine would stall....this is even with the IAC and TPS set.
I noticed that the car had 255/50 tires up front and 245/50's in back. I switched those. Car looks alot better now with the big tires in the back, lol. After doing that, adjusting the brake switch and getting the speedo working, I noticed my true speed was about 78mph at 3200 rpm. Im on my way...TC must be locking now.
Today, I plugged off the pcv line on both ends, since a pcv system is pointless on a car with breathers on both sides, and pretty much draws air straight through the breathers, up the crankcase, and into the manifold. Basically just serves as a huge vacuum leak. I also noticed I hadnt sealed the injector leaks very well. I did this time. A couple header bolts were kind of loose on the passenger side. I tightened them, and the exhaust leak sound has diminished a bit. I pulled the EGR valve to make sure it was working. It is. I used silicone on both sides of the EGR gasket when I reinstalled it. I also used gasgacinch on both sides of the vacuum block gasket. The EGR filter was filthy and clogged. I cleaned it.
Now, when I was adjusting my IAC, I could actually get the engine to idle at 500 rpm's smoothly with the connector off. A huge achievment for this car! I went through the cycle of setting the IAC and TPS till everything was perfect. Now the engine FINALLY idles pretty smoothly. Before it sounded like it had a top fuel cam in it. Now Im going to drive home, and i have feeling that my mileage will be improved as a by product of getting the other things fixed.
Wish me luck!

 

[murphster]

One other thing to consider is that the high fuel pressure you had before, 50psi at idle, probably hurt gas mileage a decent amount. This could have been one of the main things affecting the idle quality and part throttle driveability too. I was running high fuel pressure (because of small injectors) with a high stall non-lockup convertor previously and was getting horrible gas mileage. I just changed to bigger injectors (50's) and now have lower fuel pressure also the convertor now locks up at cruise so I'm expecting to see better gas mileage.

 

[VadersV6]

yeah, the pressure could have been an issue. After the drive last night and back to work, Im still sucking up gas like a freight train. I wonder if I have a non lockup convertor. Guess Ill know for sure when I get a scanmaster. Car runs really good though.

 

[VadersV6]

Now I have oil dripping on my exhaust somewhere. I cant seem to find it. It drips, makes a cloud of smoke, chokes me half to death, and makes my car smell like burnt oil all the time. The saga continues.....

 

[ledzeppac]

Join the Club of HELL!

Take off your intercooler and see if it is full of oil. Then look at the wheel of the turbo and check for shaft play and excessive oil. Your turbo might be pushing oil through your engine...

I suspect mine is doing the same.

Phil

 

[wiked87gn]

check the valve cover gaskets specially in the rear, after the car sits for a long time they go brittle and get loose that maybe your problem..., turbo is not leaking oil i made sure of that before i got the car...