Hesitation at Startup

Reply Subscribe

Thread Tools

Search this Thread

09-22-2002, 09:56 PM

RX7Aggie

Senior Member

Thread Starter

Join Date: Apr 2002

Location: NASA/JSC - Clear Lake, TX

Posts: 870

Any one else had this problem? I start my car after its been sitting for a day or so and it idles around 1500 - 2000 RPM. I step on the gas to rev it up, and it starts hesitating and rpm drops. I keep on lightly pressing on the gas, and it hesitates more. If I pump the gas hard, it gets going normal. I'm guessing pressure loss in the fuel system, maybe air?

My '86 N/A always revved up high (3000 rpm) at startup for 15 sec or so, then dropped down to idle. My turbo doesn't. Any suggestions?

09-22-2002, 09:59 PM

rotarychainsaw

Senior Member

Join Date: Nov 2001

Location: South Jersey

Posts: 888

It gets better after it warms up?

09-22-2002, 10:10 PM

evilT2

Senior Member

Join Date: Jul 2002

Posts: 563

sounds like a vacuum leak

09-22-2002, 11:12 PM

RX7Aggie

Senior Member

Thread Starter

Join Date: Apr 2002

Location: NASA/JSC - Clear Lake, TX

Posts: 870

Quote:

Originally Posted by rotarychainsaw' date='Sep 23 2002, 05:59 AM

It gets better after it warms up?

yeah, runs fine after a few hard pumps. If i pump it too hard, though, it will stall out. when I'm driving, it runs great. haven't raced anyone yet, but definitely faster than my '86 NA, or my moms shall I say. (she couldn't bear to see it leave the family, so she bought it from me. It was my first car.)

Anyway, i've got 875 mi on the new engine, 125 more to go on the break in. Then I will reallly take it for a spin. Right now the most boost i've hit is about 7 psi, keeping it under 6000 rpm.

09-23-2002, 08:37 AM

rotarychainsaw

Senior Member

Join Date: Nov 2001

Location: South Jersey

Posts: 888

Sounds like a TPS prob, but i dont think it would get better after the car warmed up. then again i might be paranoid because my TPS has been givin me crap.

09-23-2002, 03:50 PM

Rob x-7

Super Moderator

Join Date: Feb 2002

Location: Amityville, New York

Posts: 12,288

TPS, or maybe even water thermo sensor.

09-23-2002, 05:18 PM

fstedy

Member

Join Date: Jul 2002

Posts: 58

I'v had a similar problem after installing a homemade bleed off valve (in fuel line for leaking injectors). After I removed it I had throtle response go back to normal... Check your fuel line connections.

09-23-2002, 05:34 PM

j9fd3s

Senior Member

Join Date: May 2002

Location: California

Posts: 22,465

is the aws hooked up? mine was not and it runs really rich without the extra air.

mike

09-23-2002, 05:37 PM

Turbo II

omghi2u

Join Date: Mar 2002

Location: Los Angeles, CA

Posts: 7,259

Quote:

Originally Posted by Rob x-7' date='Sep 23 2002, 03:50 PM

water thermo sensor.

im not being an *** im just curious cause ive never heard that one. how do u figure its the water thermo sensor. again im just curious

09-23-2002, 05:46 PM

#10

Rob x-7

Super Moderator

Join Date: Feb 2002

Location: Amityville, New York

Posts: 12,288

A bad water thermo sensor will give you a hard start problem, another RX-7 owner had a hard start problem, they tried everything and couldnt figure it out, I told him to test the water thermo sensor, and it ended up that it was almost unplugged, he plugged it back in and never had another problem again, if the sensor isnt operating correctly, the computer doesnt know if the car is cold or not.