blazerman

ok, got my 1990 s5 vert a few months back. had some problems with the cooling system but i think it seems to be good for now. but my new problem is cold starts in the morning.

it just started to get cold here in the mornings (38-40). car used to crank fine when it was still warmer in the mornings. but here lately it has been becoming more of a chore to get it going. sunday my blazer broke down so i had to break out the rx7 that evening. started fine that afternoon after sitting for about 2-3 weeks parked.

went out monday orning to crank it so it could warm up and defrost the windows while i was getting ready. took a few minutes to get it going. but then it was fine for the rest of the day.

tuesday morning, same thing took a little longer to get started. went to lunch about 11 and then it took about 5 minutes to crank then smoked real bad for a few from the fuel.

then comes yesterday. went out to go to work and it would not crank. tried for a while and nothing. it acted like it wanted to but jst wouldnt ever fire. the battery seemed to be getting weak so i pulled it out real quick and threw in a optima red top i had laying around. still no start. so i had no choice but to call into work late till i could figure something out.

let it sit for about an hour and tried again. still a no go. so i started to work on the blazer to get it going so i could get to work. well, i never ended up going to work. what started as a hour jon on the blazer ended up being close to 5 hours.

but around 2 or so i tried the 7 again just for the hell of it, and guess what?

the damn thing fired right up on the first try.



so, what im trying to find out is there any tricks, tips or anything to help this thing crank better in the mornings? i love this car most of the time. but i need something that i know will start in the morning as my blazer is supposed to be parked since its on air ride and its supposed to be the toy.


sorry for the long story, just wanted to get as much info out there as possible.

also, all i have done to the car is new thermostat and radiator. also installed a switch for the fuel pump. guess i got that hooked up right. jsut looking for some help. really dont want to sell this car but if thats what it comes down to i guess ill have to go that route.

thanks

FelixIsGod29X

iTrader: (50)

How many miles on her? Any kind of hot start problems? Recent tune up?


When it doubt.....pop start it

Also i see a 2009 civic in your sig, why not daily drive that?

clokker

iTrader: (2)

I'd look at your battery cables/connections and the health of the battery itself.
38-40° ain't that cold and your car should fire right up at even lower temps.

blazerman

the civic is the wifes. she is a teacher so i can drive it during the summer.

usually on hot starts it is fine. when i got it i replaced the plugs, oil, and all other fluids. only thing left is the fuel filter.


first thing i checked when i first got the car. i work at a parts house so i got a new battery just to be safe since i didnt know how old the battery that was in it was.


im going to try the fuel filter and see how it does after that.

my only other worry/concern is that right after the fuel filter right before it goes to the moter there is a weird fitting in the lines. i posted back when i got it and someone said it was a part mazdatrix used to offer. it is 2 straight brass fittings that is connected in the middle. kinda like an H. someone said it was made to help bleed of the pressure from the feed line after shut down.

could that actually be causing any kind of problems? all my buddies around here that have had rx7's have never seen one before.

clokker

iTrader: (2)

That's a bandaid that bleeds off line pressure so marginal injectors don't flood the engine when it's off.
I'd delete it and have the injectors refurbished.

It ain't the fuel filter- although by all means, replace it anyway...can't hurt.
A bad filter would be a problem no matter the temp and you've already said that warm ambient starting is OK.

You say you've already replaced the battery but what about the cables?

blazerman

didnt replace them. only the ends at the battery. the rest of them looked to be fine.

also, what about the oil weight?i know some vehicles if you run a thicker weight in them they can be a little harder to start in cooler temps. since the colder the temp the thinker the oil. im running gtx 20w50 right now.

clokker

iTrader: (2)

Well, I run 10w/30 year round but again, 38-40° shouldn't be cold enough to give 20w/50 any problems.
I think the outside temp might be a red herring here and it's just coincidence that your starting trouble began as the temps lowered.

Could be your starter is going bad.
Could be your alternator ain't up to snuff.
Could be your battery cables are fritzy (yeah, I know...).

Amur_

I had this problem a few years ago with an '86 NA. As we got closer to winter, first thing on cold mornings she was very hard, later impossible, to start. Later in the day when it was warmer, she'd fire up like normal.

The cause was a broken water thermo sensor (not to be confused with the water thermo valve.) On the s4 this sensor plugs into the coolant filler neck below the thermostat. I had unwittingly broken the sensor some time before when I was tightening the alternator down.

The sensor monitors coolant temperature. It tells the ecu if the coolant is cold or warm and the engine uses that to determine the air/fuel mixture. When I broke the sensor the ecu switched to a map that assumed it was a nice, sunny, California afternoon out, making it impossible to start during a typical Canadian winter.

The sensor was surprisingly cheap for a Mazda part. I'm trying to find it now in the s5 FSM for you...


[edit] Page F1-75 of the 1990 FSM has a sort-of-helpful diagram that includes the sensor.

blazerman

ill have to check out that sensor. ive seen a few threads mentioning it.

also, just got in from changing the fuel filter and removing that bleeder fitting.

weird, i have a fuel pump shut off switch. before when i would turn it off the car would die right then. but now with the fitting gone, it will run for a little bit after turning the pump off like i have read it is supposed to. so im going to see how it does now when it gets cooler again. of course here its hard to see how it will do in the cold because here lately its either 50-60 in the mornings or around 40. stupid weather.

mikem1959

iTrader: (2)

It sounds to me like the car has leaking injectors and is flooding? It also sounds like this has been a problem with this car for a while,hence the fuel pressure bleeder.Maybe you should remove injectors and have them checked and possibly rebuilt? Just my thoughts,GOOD LUCK !!

Amur_

Except a flooded rotary doesn't clear if you just let it sit for a while. That's why every de-flooding write-up instructs that the spark plugs must be removed and the engine cranked to expel the excess fuel.

clokker

iTrader: (2)

Excellent suggestion.

Wish I'd thought of it.