Falcon

I doubt it's a lack of fuel pressure as my other car which only switches the pump on at cranking puts up about 45PSI. in about a quarter of a second and fires up immediately to run at about 1500 RPM cold.
 

I have a fuel pressure gauge mounted on the fuel filter outlet, and have observed that my '90 model (gen 2 NA motor) seems to work the same.
Ignition on - nothing.  Turn the key and 40+ psi is there instantly, but AFAIK my car has never stumbled on the first cold start. 
 

Lumix
I actually followed this procedure last week. Page EG-217 of the workshop manual. Jumper +B and FP, turn ignition switch on. I could hear the fuel returning/recirculating, felt the fuel line above the fuel filter. Removed the jumper and started the car and it stumbled. I will do the procedure again tomorrow morning to confirm the result.

Leave the fuel pump running when cranking it.

Reddtarga

Falcon

I doubt it's a lack of fuel pressure as my other car which only switches the pump on at cranking puts up about 45PSI. in about a quarter of a second and fires up immediately to run at about 1500 RPM cold.
 

I have a fuel pressure gauge mounted on the fuel filter outlet, and have observed that my '90 model (gen 2 NA motor) seems to work the same.
Ignition on - nothing.  Turn the key and 40+ psi is there instantly, but AFAIK my car has never stumbled on the first cold start. 
 

It is not a spark issue, base on what I read here or air flow issue unless there is a faulty MAF which does make sense if it starts the 2nd time, Engine need air, spark and fuel for it to start. The ECU control cold start fuel mixture for starting up which is called open loop. It's not the Oyx sensor, that has to heat up first and this happen only when the motor is running. So it has to be a fuel issue. Quarter of a second fuel pump prime when cranking would be fine if there is no PSI lost in the fuel rail. remember the fuel regulators in these car are 20 to 25 years old. The cold start injector only give fuel in a pre crank starting then it straight to the main injectors. For example I'm installing a links I will not use the cold start injector as suggested by Links tuner. I will prim the fuel pump first so the fuel rail is at 45psi. Then the injector duty cycle pulses it with the first crank enrichment fuel, then post start enrichment and onto warm up enrichment. This only works correctly is fuel pressure is right, other wise your ECU fuel table will be lean. This will cause a first startup to stumble. If it is a gen 3 could be a faulty Map sensor which give a difference table reading for the ECU to get it info from.

I think the same thing, 92 Hard Top. The fuel pump may be getting a bit old, so when cold, takes a couple of seconds to get the pressure up.

You could try replacing the fuel pump.

Thanks everyone for the input so far. Still looking into the fuel reg, looking into replacing the vacuum hoses, also going to find a vacuum sensor I can borrow for testing. Want to eliminate a few more things before I start looking at the fuel pump.
 
The annoying thing about this issue is the car started OKish this morning after sitting for almost 18hrs. I started it went to 500rpm hesitated for a split second and went up to 1500rpm.
 
 

I'm not 100% sure it's the fuel pump, I've just came back from overseas, 99 MR2 has been parked up for a total of 6wks, low fuel, soon as I got home I put keys in ignition, crank over and it started within a second, didn't stutter or hesitate once.
But as I stated earlier up, mine only does it occasionally. I'm still dumb founded what the cause maybe.

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I had a fuel pump fail in a Commodore and it failed slowly and mainly didn't work well on cold mornings. It failed completely eventually and the intermittent start issues disappeared when the replacement pump was fitted.

I would take a lot of convincing to it being a fuel pump. I fitted a new fuel pump (genuine from Toyota ).to my
1998 Bathurst a very few thousand km. ago. It still stumbles on rare occasions at cold start but has perfectly good
fuel pressure.

Falcon
I would take a lot of convincing to it being a fuel pump. I fitted a new fuel pump (genuine from Toyota ).to my
1998 Bathurst a very few thousand km. ago. It still stumbles on rare occasions at cold start but has perfectly good
fuel pressure.

What prompted you to replace your fuel pump?

Was about 14 years old and had pumped over 100,000 km. worth of fuel.
Didn't relish being stuck on side of road or at the mercy of some garage that had never seen an MR2
much less worked on one.
Fair chance it will run for over another 100,000 km.