IanS

iTrader: (4)

Replaced AFM, old one was shot. Put new one on, and still had problems. Found the vac leak and fixed that. Also checked the TPS and adjusted it a tiny bit. It was really close but I got it closer to what it was supposed to be just to make sure.

NOW, the car wants to start but wont until I pump the gas a few times or hold it down just a tad bit. When it does start, it will not hold idle by itself (must use throttle) and runs rich as hell.

You know how it sounds when you first unflood it and it misses and makes weird noises? It makes that noise all the time UNTIL right at 3500 RPM when it cleans itself up and runs like a bad **** (in a good way). It kinda seems like my primary injectors are sticking open or something. If the primaries were sticking open and running rich like this, when the secondaries kick on would it run considerably better all of a sudden?

Any/all help is appreciated. BTW I am an FC noob so it would be great if you could 'tard it down for me a bit. Thanks.


Oh yeah engine is S4 NA from a vert in an 87 TII body.

IanS

iTrader: (4)

Update: I started adjusting things that I thought COULD change the idle speed. I got it to idle although its hunting pretty bad. Gonna search for vac leaks again and hopefully this is all that is wrong.

Also figured out that I need to adjust the clutch pedal because it is engaging right off the floor. Feels a bit squishy but whatever. I can replace the master cylinder later on. The brakes also feel pretty squishy and are very weak. Not really sure on whats going on there. I know no one actually cares, I am simply writing all this for my own records.

....thanks for the help...

Ice_Wolf

That's pretty odd sounding Ian. Have you compression tested the motor to ensure that everything is ok? From the sounds of it it seems like the injectors were leaky, but odd that it runs perfectly fine above 3500 RPM. Possibly that it is running rich until the 5th and 6th ports open up and once it gets more air it's fine? Did you possibly try to deactivate the 5th and 6th ports and see what happens then at 3500 RPM? If it still stumbles and such once they're closed but is fine when they're open it'd seem much more like a air/fuel ratio problem. At least then you'd have a good idea that either the injectors are bad or something else.

lonewolfrx

i have the same problem

IanS

iTrader: (4)

Compression has been checked previously but I do plan on checking it again tomorrow just to make sure. The fact that it idles by itself right now is nice so I can check for coolant leaks, etc.

It really does seem like it is running too rich until it gets up high. On the other hand, if I rev it up to say 2K and slam on the gas it rockets up very fast like it should. It seems to react with either the secondary injectors or the extra 2 throttle butterflies.

Ice_Wolf

Yea, that's why I was thinking maybe it was too rich and one you were letting the extra air in that it was balancing itself out and then running fine. I'd say try to deactivate the 5th and 6th ports once and rev it up and see if it still does fine or if it stumbles like you say. Also, you could always check the primaries to make sure they aren't leaking. Just secure them to the fuel rail and grab a bucket and turn on the ignition and watch to see if they drip or if the spray pattern is goofed up.

IanS

iTrader: (4)

So, lets say that the TPS adjusts fuel, and the set screw on top of the throttle body adjusts air. I got it to idle ok by itself although extremely rich and it is at 1250 for engine speed. It starts a lil rough and after a little bit it starts running fairly smooth but at 1250 like stated before. I honestly have no idea what the TPS is actually set at I was just trying to make it work right lol.

Sesshoumaru

iTrader: (1)

there is an idle enrichment screw

adjust it to lean/richen your idle.

IanS

iTrader: (4)

Yup, all is good. Steve helped me out for some gas money.

Although it still runs weird until it warms up. I am thinking it may have something to do with the coolant temp sensor being MIA. I guess it apparently does something as far as cold startup is concerned.

my first fc

iTrader: (1)

hey i just fixed the idle problem on my 89 gxl my problem was that it would idle between 800 and 1200rpm i couldn't find vacuum leaks, but what i did find made me feel really stupid, i don't know about u guys but i have no clamp on the intake, where the shoulder part of the intake meets the actual intake tube (ur intake should be 2 large hoses one side leads to the filter other leads to the throttle body u should be able to separate the hose into two pieces) anyway the car was warming up and the idle started to surge once again and i just pushed the two tubes together and it stalled i had my brother start the car and keep it going as i pushed the tubes together and it idled perfect didn't surge or anything later i found out there is a sensor in the intake and i pulled it out and cleaned the connections and it idles perfect at 720 doesn't budge and it stopped idling at 5,000 when its cold so it turns out there was a leak in the intake

i figured i would tell everyone who has the same problems that are having no luck

arghx

iTrader: (3)

your thermowax/fast idle system is not functioning correctly most likely, possibly because it has been removed or tampered with. If that's not working the car will probably stall when it's cold. Believe it or not, people consider this a beneficial "mod"

do a search for thermowax . there is a lot of stuff on here about it with diagrams etc, especially posts by hailers

IanS

iTrader: (4)

Thanks for the info guys. I will ask the previous owner if the thermowax/fast idle system was removed or changed. In all reality I may have changed it messing with stuff i shouldnt have. I will do the suggested search and learn about how this works and update my findings.

Thinking more about this it does make sense that the fast idle (assuming for cold starts) has been removed since I started it the other day inside a 68* shop.