Weird 'miss' when i start car while engine is warm

87silverbullitt

87silverbullitt

I
Aug 15, 2008
75
0
0
Navan, Ontario
So here's the deal: two days in a row now its been pretty hot outside, around 30 degrees celsius, and when i first start up(engine cold) and drive my car its fine, runs amazing. But, if i say park my car and shut it off for around 30 minutes or so and then go to start it back up (engine still hot), the motor get this huge 'miss' every revolution and you can hear it gradually increase as my rpm increases.

Whenever i park my car before i go to bed, the next morning since the engine has had time to cool down, it's always running fine after, but still gets the miss if i start it up while its warm. Im confused on what to do.

The CEL is not on, i havent checked it for codes yet but i will in the morning.
 
jetjock

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
What Nick said. Toyota uses "residual pressure" but I prefer Bosch terms. Keeping the fuel under pressure raises its boiling point. Same principle as the cooling system. The sole reason is to prevent vapor formation 15-45 minutes or so after shutdown.
 
Nick M

Nick M

Black Rifles Matter
Sep 9, 2005
8,873
37
48
U.S.
www.ebay.com
My VSV froze, which isn't too uncommon for the VSV's. It is behind the alternator. I did a backyard test instead of an electrical check because of the location. I let it sit 15 minutes where it had trouble with the restart and rough idle. I pulled off the vacuum line to the regulator, and it had vacuum when it shouldn't have. And when I took it off and the pressure went up, the idle smoothed right out.
 
87silverbullitt

87silverbullitt

I
Aug 15, 2008
75
0
0
Navan, Ontario
So basically i could possibly have to replace my VSV which i've already replaced not to long ago? How did i get the motor to stop this in hot weather? It always lacks power whenever this 'miss' happens and makes my car sound like a subaru, an unhealthy one at that. Oh and its not hard to start after it warms up, its just the bad miss, steady popping out the exhaust
 
jetjock

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Was there some part of check rest pressue you didn't understand? I didn't mention the FPU system because it's not as critical as a loss of RP and many people run without it. Wouldn't hurt to make sure it's working though.
 
jetjock

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Good. Means it wasn't a total loss.

OP: If you can't measure fuel pressure pop the plastic top off the fuel damper and look at the little screw on top. As long as there's decent fuel pressure it'll be extended. If it quickly drops after the engine is turned off (or the fuel pump is unjumped in the diag block) you're losing rest pressure. Not the most accurate method but better than nothing...
 
87silverbullitt

87silverbullitt

I
Aug 15, 2008
75
0
0
Navan, Ontario
Update: So today once again my car did the same thing, however when i parked it when i got to work it had time to cool down. On my lunchbreak i left with the car again, started it up and everything seemed fine again as usual. 5 minutes after i start driving i notice my 'e-brake/brake fluid' light come on and also my battery light came on. I know my handbrake was all the way down and i even topped up my brake fluid reservoir and the dash light never shut off. I tried to poke around and figure out why my battery light came on, but im stumped because the car isnt showing any signs of loss of electrical power.

Also i checked my codes tonight and got a Code 31, 32, 34, and 42.

Oh and thanks jetjock for giving me a quick way to check for losing rest pressure, ill have a look at it tomorrow.
 
You must log in or register to reply here.
Top Bottom