Vehicle is a 83' Olds Delta 88 Royale Brougham with the 5.0 & 4spd auto, 230k miles on motor

Heres the problem:

When I first started driving this thing a couple years ago all I had to do was shift to first, smash that pedal deep into the carpet and voilą I created a smoke machine. But over the last year Ive been loosing power steadily to the point it was hard to keep up with the speed of traffic (were talking 25+ second 0-60s). I knew my intake manifold gasket had a leak so we checked vacuum pressure, and it was dismal at a lowly 9bls. So over the last month me and my disabled father replaced the intake manifold gasket (when we first pulled the intake manifold we were amazed to find no sludge at all, the engine looked like it has 20k miles!), the heater valve, cap, roater, plugs, wires, fuel filter and other odds and ends. After we got it torqued back down we tuned the carb, set the timing to 21 degrees and replaced all vacuum lines useing the sticker that came mounted on the fan as a map to route the vacuum lines. But once we fired em' back up he ran like TOTAL CRAP. (I'm running a dump exhaust with the cat strait piped and no exhaust after where the cat would of ended). The exhaust sounds like a freikin tractor now (sounded muscley before), runs rough, idles real rough, and worst of all I now got worse power than before the gasket job
[FONT=Comic Sans MS]We have since quadruple checked every system, vacuum lines, ignition, timing, carb, fuel delivery, everything, and everything shows up good.

We ran a compression check a few days ago and the numbers read:

Cyl 1: 175
Cyl 2: 164
Cyl 3: 168
Cyl 4: 169
Cyl 5: 170
Cyl 6: 170
Cyl 7: 174
Cyl 8: 175

We are completely stumped guys, some good "olds" school *wink* opinions would sure be appreciated!

Your friend Joe Dirt

 

Are the secondaries opening? Is the catalyst clogged? Also I cleaned up all that blue colored mess you typed with.

 

Timing chain,vacumn leak?

 

@ Chicago- Carb is operating normally, secondary's are no issue, the way its running it acts like it has a MAJOR vacuum leak. Parrdon my ignorance, but what is a catalyst? & thank you for fixing my text.

@65Cutlass- I got around 19 pounds of vacuum pressure. We messed with the timing, and ended up setting it at 21 degrees. The timing chain was replaced in June 2011. Before I tore it apart for the intake manifold fix it was low on power but didn't have the issues it dose now.

Would you guys like me to post a video so you can better understand the problems its giving me?

 

Catalyst also known as catalytic converter,i'd check exhaust back pressure you can do it by putting a pressure gauge in the o2 bung and look for less than say 5 psi wot under load,or even easier by dropping the exh at the exh manifolds and drive it see if any change.can't do videos or pics.You didn't say if fuel pressure is good.Also 1983 is known as c3 computer command control therefore has a pcm ie check engine lite.

 

I just read the tread again running rich like it has a vacuum leak and 19 pounds of vacuum pressure?Is this for real?

 

So it started running like total crap just after all the work you did?
If so, triple check vacuum connections and such.
Plug wires back on in correct Olds order?
Carb nuts snug but not overtightened to warp the base?
It is still on the computer? If so any codes?

 

@65 Cutlass, in my post I wrote: "I'm running a dump exhaust with the cat strait piped and no exhaust after where the cat would of ended" so there is no catalyst (Ive always referred to it as a "cat" or "catalytic converter") to be plugged up. We quadruple checked vacuum lines according to the GM diagram for the 83' Olds 307, all good, + a ton of new sensors & all new vacuum lines. No check engine light, it isn't throwing any codes.

@ Lady72: we cleaned & inspected the carb very well, all vacuum lines are new & attached correctly. Carb is installed correctly. Had a machine shop check the manifold while it was removed, no warping at all. I installed new plug wires after the gasket fix, distributor is in right position, and plugs are all installed in correct locations.

 

You can't remove the catalytic converter if you're running the original CCC carb. That is one of your problems.

 

Is the mc soleniod working,also maybe disturbed some debris in carb when off for intake gasket repair.

 

Sure you can. The cat doesn't effect the CCC system at all. Neither does the A.I.R. system or a bunch of the other garbage under the hood. Not that any of this is the op's problem, but I just wanted to mention it for clarity's sake.

 

I don't know whats been modified(ie) removed more info may help.I recall on those years the purge valve causing major running rich condition.That being said,DoubleV is correct removing the cat will not effect the c3 system,but removing the A.I.R system and a bunch of other garbage will.if the pcm is still connected and operational the check engine light will be on and it will not go into closed loop.

 

That's not accurate. The only emissions stuff you really need to run on the computer is the EGR system. AIR system, EFE system, vapor cannister stuff, RVB, ILC ( with associated other gizmos ), can all be scrapped and the computer would never know the difference.

 

I know this to be true, Ive had the air pump disconnected for about 2 years. Runs no different, just a slight increase in responsiveness. I know the computer isn't a very big part of this motor. Most of the sensors are mechanical and vacuum operated.

 

@65Cutlass -The carb is good, before we reinstalled we cleaned it thoroughly, and of course we properly removed, cleaned, protected, and reinstalled it. What is an MC Solenoid?

 

Also, besides for the air pump being disconnected everything is factory except for a measly valve cover breather

 

The MCS is mixture control solenoid. It oscillates a certain amount of times per second metering in the fuel that the computer wants, based on o2 sensor readings.
The MCS has to be adjusted after service. It is described in the CSM - you need a regular dwell meter to set it.

 

outlaw88 sure you can remove the airpump belt and the pcm will not be the wiser.just trying to help here and not start a pissin' match.From what i recall, if the pcm is operational it needs to see curcuit continiuity on some systems or it will turn on the mil and not function properly.try un hooking the wiring to the carburater.On another note every 2 years its required to do a smog test,(for others not living in CA) any altered emission components will fail.

 

To clarify( try un hooking the carburater wiring) i was referring was about turning on the mil.

 

I would never remove the catalytic converter without also removing the smog pump, EGR valve and all of the other emissions equipment.

As far as I know, removing the catalytic converter will give you a bad O2 sensor reading. Which will effect your mixture control solenoid. Ultimately, it isn't a good idea to mess with factory settings unless you go all the way.

 

Removing the cat will not give you bad O2 sensor readings. The O2 sensor takes it's readings well before the cat. I assure to everyone who cares to know; The CCC system requires NO emissions equipment except the EGR system to run correctly. Lot's of internet myths that say you need this and that, but these are just that...myths, like headers not fitting on Supremes and SMW 403's.

 

If you unhooked the MC solenoid the carb will run full rich all the time. If you unhooked the TPS, the computer will not recieve the needed throttle position information.

 

@65Cutlass -Not tryin to argue buddy, just doin my best to give you the clear info you asked for.

Yes of course the O2 Sensor is before the Cat

And I've had to smog it twice, when I do, I just slap a belt on the air pump, and bolt in my exhaust, always passes just fine

I'm going to try messing with the carb wires, EGR, PCM & MCS, thanks fellas

 

Just a thought here. If you don't know what an MC solenoid is, how do you know if the carb is good, or adjusted correctly? I suggest reading up on the control systems for your year car, and then diagnosing the problem.

 

This is a 3 year old thread, who knows if he ever figured it out. Impressive compression numbers for such high miles, exactly why I have owned so many Olds V8's over the years. Mechanically great for a ton of miles and none of that CCC nonsense up here till 86 on most vehicles. Of course all the Cutlass except the 88 model and Hurst/Olds and 442 got the sbc, not so good.