Toyota Repair: Fluctuating engine power, valve cover gasket, toyota celica

Question
Hello,

For a few weeks now I seem to have been having a problem with my car.

When I am driving, the power seems to be variable. That is, when holding the gas pedal steady the power seems to come in bursts: it surges then hesitates then surges and hesitates again. This cycle repeats approximately once or twice per second. This is not an intermittent problem, it does this most of the time. It is more noticeable at low/intermediate speeds, but it does it at highway speeds as well. The surging is quite clear but reasonably subtle. In other words, the car isn't bucking.

In addition, it seems to have less power overall than it used to. By power, I mean acceleration in response to stepping on the gas. A few weeks before it started having this lack of power problem the car seemed to have the opposite problem. That is, it had more power than expected when I stepped on the gas.

Basic Info:
1990 Toyota Celica GT
Automatic transmission
~120,000 miles

Repairs:
About two years and 5000 miles ago, long before this surging problem started, I had some repairs done at the Toyota dealer:

(1) Replaced ignition system components and spark plugs
(2) Performed BGEFI Service
(3) Replaced valve cover gasket
(4) Replaced distributor O-ring
(5) Replaced front motor mount

There is one other problem I have been having, which I think is unrelated but I will add for completeness. This started immediately after the dealer replaced front motor mount two years ago. If I take a sharp left turn at a good speed (e.g. left turn at a corner doing about 25-30 mph) I hear a vibrating/thumping noise as if the front right tire is rubbing against something. The speed of the noise sounds like it could be the tire and it seems to be coming from the front right of the car, but it could be something else. The noise definitely doesn't sound “good” so I slow down when it happens and the noise stops. Neither I nor the dealer could figure out what it might be. He said the suspension and shocks were fine.

It only does it occasionally, and usually only when I have been driving for less than a few minutes. It seems to have gotten less frequent. Right after the dealer replaced front motor mount it would do it pretty regularly, maybe once a week. Now it is only once every few months.

Any help you could give me would be much appreciated.
Thank you,
David


Answer
Hows your fuel psi, should be around 45 to 60, I had one that only time it would drop was when driving, the pump was going bad, we only found this with the gauge ran out the back side of the hood laying on the windshield, so when we drove it the needle would start jumping around 0-45.  It was a pain to find this one.

Mount, see if the bolts are tight, or if they rung one off or crossed one and it's not pulling it flush, look around and see if you can see where the mount has been rubbing.  I had a axle that made this type of noise but even under a load going forward, no tore boot just wore out, hows your bearing on that side.