'79 Seville intermittant power loss...

[dpeck]

I own a '79 Seville & I've run up against a wall (not literally). The car has always had an intermittant loss of power usually at freeway speeds. It's almost like the ignition is turned off, but all the electricals stay on. It only lasts for about 1 second or sometimes 2, and I instinctively pump the accelerator, then everything is normal again. If I keep a steady foot on the gas, it will stutter even worse, but never dies. It does this approx. every 2-3 minutes and almost always right around 70MPH. I have replaced the "computer", if that's what you call that hunk of 1979 circuits. I have also checked the injection system, the vacuum system, throttle body, to no avail.

I have seen mention of a "TID", or Technical Informational Document (I think it's called that) that Cadillac released back in 1980 regarding this particular Olds 350 engine and this particular problem. Unfortunately, only Dealerships and I think repair shops have access to these documents.

If anyone knows how to get the information from Cadillac or another source, please let me know because this "mini-stalling" is driving me NUTS!!! I have put a lot of time and $$$ into refurbishing this beauty, and this is one of the last little things that isn't right.

Any help will be greatly appreciated!

[dpeck]

An update for anyone who is interested:

Yesterday, my wonderful Seville decided that it was time to leave her owner stranded. I broke down about half way to nowhere...

It may be totally unrelated, but the power loss thing seemed to get worse. Then even worse. Then I had to pump the gas to keep it from totally dying. Then I had to floor the gas pedal to keep moving at 5mph. She made a REALLY weird squeal when I had her floored, then she quit... Now I thought it might be an overheat because I had power-flushed the cooling system the day before, but there were no fluids escaping that I could see. No coolant, no water, no steam. I had also replaced the transmission filter, pan gasket & fluid, but the tranny seemed fine (I don't know squat about transmissions).

I'm guessing one of the fuel pumps went out. I can still hear one of them when I turn the ignition on.

So I suppose I'll try to figure it out this weekend, if the car is still in one piece, that is. And I had just received the new wire hubcaps that I ordered. She was lookin' REAL sharp. Oh well, that's my luck.

[79 Seville]

My '79 Olds 350 (Seville) does the same thing; that is, it cuts out sometimes around 65 or 70 mph for about a second. I would sure be interested in the cause and solution too.

[MagicRat]

I would suggest the basic diagnosis. If your car is dead, check for spark. If yes, then work on the fuel system.
You might have a mostly blocked fuel filter, where there is just enough fuel flowing to keep things going around town, but out on the highway, when the fuel flow is higher, there is not enough flow and fuel pressure goes down.

A weak fuel pump would do the same thing.
If it is the fuel filter make surre the gas tank is clean inside and not a mass of rust already to block the next filter.

[CADIBROUGHAM]

I THINK YOUR CADI HAS AN ENECTRONIC FUEL PUMP IF IT DOES THE FUEL PUMP MAY BE SHORTING OUT AND NEED TO BE REPLACED I HAS TO REPLACE MINE IN MY 91 SEVILLE BECAUSE IT WOULD SHORT OUT WHEN I STARTED TO ACCLERATE ANT TO KEEP IT GOING I HAD TO PUMP THE PEDAL. DONT FORGET THE FUEL FILTER. ALOT OF PEOPLE FORGET THAT THE FUEL YOU PUT IN YOUR CAR IS UNFILTERED AND AFTER 40000MILES THE FILTER IS PROBAbly completly RESTRICTED. NOW THE FUEL PUMP HASTO WORK TWO TO THREE TIMES AS HARD.

[AcesHighJoker]

ok i can almost gurantee that what happened is a total blocage of your fuel filter or in the line.... the squealing was probably your alternator bogging down due to the draw from your fuel pump. Check your filter first, then check your line by turning on the ignition with your line in a bucket or whatnot.... i suggest putting it into somthing because we started a fire dooing this... dont worry we only lost a seat from a 69 impala that had a bunch of holes in it. that should solve your problem.