hey, my auto will sometimes stall out on me while under full amp, and running perfect. the IAC seems to be ok, and the tps is corrtect. any suggestions? also, in city,stop and go driving my car loses colts pretty quiclkly. i have to foot brake it. i have no system, no under drive pulleys, and new alternator. problem is still not fixed. alternator is stock replacement. not sure what amp stock is.

 

I went through six alts in a year from advanced auto parts (wouldn't by chance be where its from?) Fixed my problem with a powermaster alt from summit. Never had luck with the chain auto parts stores alts.Oh, I didn't pay for all six.

 

well, it's a rebuilt one from autozone. lol if it goes, i'll get a 140 volt alt. that wont be too much will it?

 

140 volt one will!, J/K. 140 Amp alternator will be more then enough. Fix the problem with the low voltage and your stalling probs. will probably go away.

 

lol, i couldn't remember if they were rated at volts or amps... so i guessed. haha well, I'm hoping the 140 wont be too much. at normal driving, I'm around 14 volts, but drops below 12 in stop and go city. who makes the best alternator?? also, it will fix my stalling in city driving, but sometimes I'll be at a stop light (non stop and go) and have full volts (14 or so), and it will idle fine, untill i go to hit the gas, and it just stalls right out, for no apparent reason. i can't figure it out. the car runs fine, doesn't act up, and it just stalls for no reason. it stalls just like a manual would, once i start to go again from stop. it doesn't do this much, but still the 2 times a month or so still has me stumped.

 

hmmm... Some of the cheap alternators have alot of trouble maintaining voltage under loads. I had a bosch unit and that would always let the battery run down then the lights/rear defroster where on. Low voltage can cause problems but if it manages to hold at least 12 volts at idle then the stalling problem is definatly not related.

 

well, I'm maybe considering the cam not liking stock idle with low volts. i have a different cam. a ramjet 350 GM cam. nothing big, but more lopey than the stock cam. thing is, i can't figure out how to raise my idle right. any suggestions?

 

How is the idle? Its erratic i take it? The way to properly raise the idle is by editing the ecms calibration. You could raise the base idle setting up untill you have around 10-15 IAC counts. This will help by taking some of the idle control out of the ecms hands and it might help prevent stalls when the IAC is moved toward the closed position. Youll need a scanner to do this, though.

 

my idle is fine, untill i start loosing volts. then it's jumpy. every time i set the screw out, the iac would correct it and it's close to all the way out now, and still idling at 650 in gear when up to full temp (160*)

 

Mayve it is a voltage problem. Off the top of my head, the IAC is disabled when the voltage drops below something like 8.5 volts. Run the car with the accesories on and use a DVM to see what the voltage is at the battery.

 

i've used my dvm on the battery and it reads good, and i don't have many accessories to turn on. it just seems that the 2nd fan kicks on at around 160* F and thats when the low voltage occurs. i could put the fan on a seperate switch, but if i didn't run it right, it'd look ghetto

 

Try performing the test with the car warm and idling and rear defroster, fans, ac, and headlights on and then measure what the voltage is. It probably wont be much more then 12.5-13 volts with a stock type alternator but that will give you an idea of what the worst case senario is with the car. This should lead you in the right direction as to whether low voltage is responsible for your problems.

 

u think that hooking the 2nd fan to a switch would help?

 

See what the voltage drop is when the system is under the load stated above. Even with a cheap alternator, the voltage shouldnt drop below 12 volts at idle and the alternator should be able to sustain enough voltage to keep the battery from draining when the car is moving.

 

the volts never get below 12... just right at 12, and it drops and rises with rpm level change randomly. my motor doesn't like to idle at 500rpm in gear at stop, so it bounces the rpm up and down a bit. i guess i just need to figure out how to raise my rpm like 75-100 rpm in gear at idle. how did you say the best way to go about it is?

 

I know what you mean, the stock idle speed for my car was around 550 rpm and the engine didnt like it too much. Happiest around 750 or so.

Get equipment to do some prom burning. Not only can you take care of the idle, you can also change when the fan comes on and do lots of other stuff. Also not a bad idea to minimize the IAC counts by tinkering with the base idle speed once youve decided on where to make the desired idle speed. This way the idle isnt entirely controlled by the computer.

 

whoa, how do i do prom burning? anyh easier ways?

 

If you want you can put out an add on the clasifieds with what type of ecm you have+what you want done or contact a 'professional tuner' as they like to call them. Youll ahve to make some minor mods to the Memcal to accept a chip, send them your Memcal to be erased and reprogramed, or purchase a memcal with the chip already programmed. One of the things I never liked is sometimes with the chips used is that they can fail or be scrambled. Ive had T-storms wreak havock with some eeproms that Ive had. Also had some fail while driving the car. Not fun and w/o a burner youd be SOL. Non the less, there are people who will do it for you for a reasonalble fee.

Heres a good link: link