G'day,
94 fd3s, situation, car runs like new.
Just had a new alternator installed.
Suddenly, the car drops in power (like not receiving fuel) when I am going from 1st to 2nd.
My mechanic, who looks after it has done vacuum leak tests and then tested the engine and seals and can not figure this one out.

Hoping someone may have a clue here.
THANKS IN ADVANCE.

 

If all you changed was the alternator, try putting the old alternator back into the car. See if your problem goes away. Obviously you'll have to figure out your charging issue, but you can rule out a bad alternator as the issue.

 

G'day,
The alternator is already gone (recycling) and it was fried.
But thank you.
These 2 mechanics are stumped, and they have looked after this vehicle since it arrived from Tokyo in 2016.

 

So the alternator was replaced, presumably because it wasn't charging correctly? From the time you start the engine to the point that it "drops in power (like not receiving fuel) when I am going from 1st to 2nd" how much engine running time has elapsed, and when that occurs, did you happen measure the voltage at the battery? Reason I ask is the symptom you described may have nothing to do with your alternator or everything to do with it.

Just a theory, but let's assume for now that your alternator isn't charging while the car is running. In that case, after a period of engine running time, the battery will become depleted and fail to supply enough current to all the electrical loads (fuel pump, coils, e-fans, etc.) required to run the engine, and at some point it will just stall. How long that takes depends on how healthy the battery is to begin with. If you get the car started & running again at idle, check the voltage at the battery posts and report back what you measured at start up, and then again over time - if you measure about 12V right after startup and it drops over time while idling, it confirms a charging system failure.

Since you have a new alternator, let's assume for now it's not defective - that leaves the alternator wiring to check. There are 4 connections at the alternator to check. The alternator ground connection is thru its case, so if the new alternator was powder coated/painted, that might impede the connection - you need metal-to-metal contact between the alt. case and engine. The next connection is the B+ power lead, that's the heavy gauge wires with the big ring lug terminal that secures to the alt. "+" power post with a nut - check for a secure connection there. The next 2x connections are in the plastic connector from the engine harness that plugs into the alternator. BOTH of those connections must be secure for the alternator to charge correctly; sometimes the plastic connector shell fails and the metal terminals within get a bit loose, and will "push back" when plugged into the alternator, causing a poor/intermittent connection resulting in no charging.

 

FYI, moved this to the main forum and changed the thread title to make it more obvious

 

G'day,
Once again, my sincere thanks for your attention.
(BTW, I am originally from Bucks Cty PA, not far from you in Elkton).

The alternator is new, but yes, it might be faulty.
The battery is new, as roadside assistance here replaced it when they diagnosed my problem.
A new battery was installed, so I could drive it up onto the flatbed to get it to the mechanic's garage.

After the replacement of the battery/alternator, I collected the vehicle, and there were no problems.
I drove it for 2 days, and starts were fine, and the performance was fine.
3rd day after, and that is when the problem started.

Yes, you are right, it is like when the alternator was dying, and it could not run the abs, i-car system, fuel pump...... and then of course it just quit.

I am printing your comment for the boys at the garage to read, as the part where you speak of in correct connections resonates well and requires checking.
New alternator requires checking, new battery needs to be checked

The car is not a daily, but out every weekend to work if not raining.
Once every 3 months, I drive 8 hours home, and it never skips a beat.
I maintain the car like it is new and always have a professional on it or under it.
It is an amazing vehicle.

I appreciate you replying to me, as this is causing extreme anxiety.
I am supposed to drive home next week.
Kind regards, Jeff

 

Forgot to add, if you have a voltmeter handy, measure voltage across the battery posts before starting - it should read between 12.3 ~ 12.6VDC with a healthy, charged battery; a little less (>11.5 V or so, but less that 12.2V) means it just needs a charge. After staring car and running at idle speed, you should be reading somewhere between 13.8 ~ 14.5VDC if the alternator & charging system is healthy.