jimbodini25

OK guys, I've been at work on this thing for a year putting it back together, and it has had a problem that I can not solve. Hopefully somebody else has had it and can tell me what needs done.

Simply put, whenver one presses the gas, the car bogs out and normally stalls. At idle it runs great, but give it any gas and it dies. Feathering the gas sometimes saves it. That is the only problem it has. and it only dies when you press the gas. When I drive it, once it's going, its fine. But if I stop at a light or whatever, when I press the gas to go, it dies.

Car has new plugs, wires, distributor cap and rotor, fuel filter, catalytic convertor w/ split air pipe, professionally rebuilt carb, and a few misc items I cant remember at the moment. Had the coils tested also, and they are fine. I just need some help. Let me know if you have any ideas, Thanks.

-Jim

jimbodini25

Would this be caused by the Throttle position sensor being bad? I replaced it before, and the car ran great afterwards, but I'm thinking perhaps it went bad again and I need to buy another. I posted a WTB in the classifieds but have yet to get any responses.

budrud

Is the accelerator pump hooked up/ working? You mentioned the carb is rebuilt maybe it got missed.

mazdaverx713b

iTrader: (91)

jim, it definatly sounds like something is askew with the carb. i'd be willing to send you a carb to try or bring the car over and we can try a different carb or two.

mazdaverx713b

iTrader: (91)

ok, i have posession of the car and worked on it a little yesterday. here's what i found: fuel pump seems to work fine, the car has new plugs and wires, and a fuel filter. in neutral, the engine runs and revs perfectly with no bogging. once the trans is put into drive or reverse, the idle will hunt slightly and the engine will begin to run rough. to get the car going, one must feather the gas very lightly and above 1500rpm the engine will not bog and will pull very hard to the redline if you shift it manually or up to 6K if you let the trans do the work. it seems that with the auto trans, power steering, ac, air pump, and alternator, the accesories are just bogging the engine. we have no vaccume leaks, a nice steady idle, great cruising abilities, just a tad rocky at times on the get go, having to feather the gas to prevent stalling. the carb was definatly rebuilt and the accelerator pump diaphram is new. any thoughts?

budrud

Maybe your idle is just set to low. I don't know what the idle is supposed to be set on a automatic but I would guess around 1000- 1200 rpm

mazdaverx713b

iTrader: (91)

supposed to be 750. its right on the money. i thought about raising it to 900 but i'm not sure if that would just bandaid the problem rather than solving it.

trochoid

iTrader: (6)

Check for flow on the AP jets. Should have a decent squirt on each side. Test can be done with engine off.

mazdaverx713b

iTrader: (91)

for this, should i just press open the primary butterflies manually at the front of the carb and look into the carb and check to see if they drip gas(with the engine off)?

mazdaverx713b

iTrader: (91)

any other thoughts on this matter?

budrud

They shouldn't just drip gas, you should get a good squirt on both sides when you work the throttle linkage

jimbodini25

Here are the #'s from emissions testing last month in case they point towards anything specific:

Emissions:......... Reading ..... Units ..... Limit
HC ................... 47.3 .......... PPM ...... 197.0
CO ................... 0.00 ......... % ......... 1.27
NO ................... 536.7 ........ PPM ...... 1440
CO2 ................. 12.9 .......... % ......... N/A

Gas cap pres. ... 27.10 ........ In H20 .... 6.00, haha.


Do those numbers look odd to anyone? Any indicators? The car passed first try on 6/8/2007. And this is with me not knowing how to tune the thing quite right.

mazdaverx713b

iTrader: (91)

well, tonight i pulled the top of the carb and cleaned all of the air bleeds and blew threw them. i checked float level height, checked needle and seat wear(both were brand new), i cleaned the float chambers, as there was tons of dirt and crap at the bottom in the circular catches, and put a lot of cleaner through the carb. still the problem persists. i may pull the carb itself and inspect teh accelerator pump diaphram. i know the carb was rebuild just months ago, but perhaps the rebuilder ripped the diaphram upon install. the ap jets also work wonderfully now, as opposed to be barely working before tonight.