an RX8er's rebuild thread
Thread Starter
what was I thinking
iTrader: (8)
Joined: Jun 2004
Posts: 2,408
Likes: 0
From: Converse, TX
ah the joys of owning an RX8
the other day I filled up with gas and on the way home the car started hesitating and eventually stalled. I manged to limp home with a series of start/stalls up to 30mph...fuel pressure was 53psi
swapped the pump assembly with a used one 9k had and that didn't resolve the issue, so I removed the purge solenoid following the DTC and that didn't do anything either. The fuel pressure seems to hold just fine...after 5 minutes it only dropped to 48psi (limit is 29psi)
I would also like to note I had the fuel leak on top of the engine block a while back that was never identified. I did replace all the lines and injectors just to be safe.
There is currently no obvious fuel leak just low pressure...need some advice
the other day I filled up with gas and on the way home the car started hesitating and eventually stalled. I manged to limp home with a series of start/stalls up to 30mph...fuel pressure was 53psi
swapped the pump assembly with a used one 9k had and that didn't resolve the issue, so I removed the purge solenoid following the DTC and that didn't do anything either. The fuel pressure seems to hold just fine...after 5 minutes it only dropped to 48psi (limit is 29psi)
I would also like to note I had the fuel leak on top of the engine block a while back that was never identified. I did replace all the lines and injectors just to be safe.
There is currently no obvious fuel leak just low pressure...need some advice
Thread Starter
what was I thinking
iTrader: (8)
Joined: Jun 2004
Posts: 2,408
Likes: 0
From: Converse, TX
I did...failed
Thread Starter
what was I thinking
iTrader: (8)
Joined: Jun 2004
Posts: 2,408
Likes: 0
From: Converse, TX
I cant verify if the relay is functioning until my wife gets home. I did ohm out the resister and it was off; should be.304 - .336 and mine tested at .7
Okay so "ohming" out the two resistors you have (both presumably work just fine) tells you that they are out of spec (.3 and yours were both .5-.7) right? So what does that mean? Problems in the wire or connector to the resistor right?
check the voltage at the pump during both low speed and high speed functions.
Its easy to do and just do it while driving the car.
How are the fuel trims during these times? As expected?
My car at rare times --immediately after fill up will not want to idle and stall out. But after just a few throttle blips it fixes itself.
Someone told me it had to do with the purge valve and the tank vent system.
Dont you need at least 58psi of pressure in the fuel system?
Its easy to do and just do it while driving the car.
How are the fuel trims during these times? As expected?
My car at rare times --immediately after fill up will not want to idle and stall out. But after just a few throttle blips it fixes itself.
Someone told me it had to do with the purge valve and the tank vent system.
Dont you need at least 58psi of pressure in the fuel system?
Last edited by olddragger; Jan 16, 2013 at 08:47 AM.
Thread Starter
what was I thinking
iTrader: (8)
Joined: Jun 2004
Posts: 2,408
Likes: 0
From: Converse, TX
ok, so either I am a dumbass or something is up
I tried to do a voltage test and it seems to be coming up 10v...should be 5v. I changed the pump relay with a spare and nothing is different (I am not 100% sure I am reading it properly though)
I did manage to get the car started but it took some convincing....lol...fuel pressure still 53psi with no noticeable leaks
I tried to do a voltage test and it seems to be coming up 10v...should be 5v. I changed the pump relay with a spare and nothing is different (I am not 100% sure I am reading it properly though)
I did manage to get the car started but it took some convincing....lol...fuel pressure still 53psi with no noticeable leaks
Thread Starter
what was I thinking
iTrader: (8)
Joined: Jun 2004
Posts: 2,408
Likes: 0
From: Converse, TX
no shorts or anything like that...I did notice when the pump first kicks on the fuel pressure is 58 then immediately drops to 53psi. Could this possibly be an injector stuck open?....that would drain more than 5psi right?
The thing would not run with that much fuel being dumped from an injectorIt is either pump output caused by a pump crapping out...or a voltage regulation problem. I would wire around the resistor pack and see what the fuel pressure does with it jacked on high....and then test the voltages and the outputs on low....it is either the resistor pack/wiring or the pump
Thread Starter
what was I thinking
iTrader: (8)
Joined: Jun 2004
Posts: 2,408
Likes: 0
From: Converse, TX
thats the thing it doesnt "run" unless I crank on it a ton. and I am just guessing with the injector, if I dont see a external leak it much be internal
when I follow the FSM I get 12v at the pump (or maybe it was 10.5...cant recall atm) but it wasnt the 3-5 like it should be.....hopefully a fresh set of eyes will help out...too many irons in the fire...lol
if I can just wire around the resister I will give that a shot in a bit.
when I follow the FSM I get 12v at the pump (or maybe it was 10.5...cant recall atm) but it wasnt the 3-5 like it should be.....hopefully a fresh set of eyes will help out...too many irons in the fire...lol
if I can just wire around the resister I will give that a shot in a bit.
Last edited by houstonrx8er; Jan 18, 2013 at 11:09 PM.