85Iroc-Z

iTrader: (4)

My car will start right up, run for half a second and then it will stall. Anybody have an idea what might be causing this?

dahn

Check the vacume hoses I had a86 chevy truck the larger hose coming out of the bottom of the carb slipped off pluged it back in ran fine.

85Iroc-Z

iTrader: (4)

There might be one or two vacuum hoses unhooked along with the valve cover elbow on the right side of the motor but the car has run with these unhooked before. Now i cant get it to stay running. I would like to buy that valve cover elbow but i cant find one anywhere.

Colts45s

you need to get that elbow as you called it cause that would be your pcv valve hose which goes from your valve cover to your intake system which if not functioning will cause your car not to idle

Damon

That's sometimes an indication of a bad MAF sensor. The computer doesn't look at the MAF signal until engine RPMs get over about 250 or so. It fires up on the starter becuase the cranking RPMs are below that point, but as soon as the motor fires and the RPMs shoot up, it references the MAF signal which, if it's flaky, will be wrong and it'll immediately kill the engine.

EASY TO TEST..... just unplug the MAF (temporarily!!) and fire it up. If it fires and holds an idle then you've found your problem. Of course, the check engine light will be on, but it'll stay running.

85Iroc-Z

iTrader: (4)

Unplugged the connector to the MAF and it ran and stayed running until i shut it off. After i tried to start it again it does exactly the same thing. What could it be now.

85Iroc-Z

iTrader: (4)

Im thinking that it is fuel related now. Took a couple plugs out and they were dry with only a little gas on the threads. What could i check to see if the problem is fuel related? Also could the IAC valve cause this to happen?

85Iroc-Z

iTrader: (4)

Anybody Know? Also this valve cover elbow that i was talking about looks like this.
http://www.paddockparts.com/Paddock/...BC0368DA3A172D

cool84

yeah thats for your pcv (positive crankcase ventilation) there should be a little plug looking thing on the oppisite valve cover with a vacuum line running from it too.

that elbow your talking about takes the air from the crankcase and sends it into the air intake on the side of the filter cover

85Iroc-Z

iTrader: (4)

Im gonna put that elbow on as soon as i find one. However i cant see this being the cause of the problem since the car has run dozens of times without stalling while it has been missing.

Outlaw28

another thing...check your fuel filter could be loaded with garbage

85Iroc-Z

iTrader: (4)

The fuel filter was replaced about a year ago. Since it was a project car and i had a tranny problem i would only push it out in the driveway and start it up every once and a while. Could the fuel filter get clogged just for the few times it has been started?

85Iroc-Z

iTrader: (4)

After spraying starting fluid in it, it will run for probably 4-5 seconds until all the starting fluid has been burnt. Even when i give it gas it revs but will then stall again. I opened the fuel lines to the motor and they had gas in them. What could it be the injectors?

85Iroc-Z

iTrader: (4)

Any ideas?

85Iroc-Z

iTrader: (4)

Still nothing? Any help would be greatly appreciated. Im running out of ideas. How about the ECM is that a posibility?

z 28 jari

iTrader: (1)

Have you check troblecodes?I have similar problems,it give code 34(maf).Somehow taking batterycables off for a moment helps.To be sure is it ecm or maf ,I need to measure maf output with oscilloscope.

85Iroc-Z

iTrader: (4)

I dont have a scan tool available to check my codes so no i havent done that yet. Ill check them when i get one. Could my fuel pump be bad even though it turns on for the 2 seconds when the key is turned?
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I cant check my codes since i dont have a scan tool. When i get one i will check them. Could my fuel pump be bad even though it turns on for the 2 seconds when i turn the key forward?

ChoobinatoR

Dude, I bet we have the same problem.
Let my 89 v8 camaro sit over the weekend and I go to start it up today for school, starter cranks fine, but engine didn't run. Later I applied some gas while starting, and it worked, but rpms dropped instantly after I took my foot off the gas pedal, to a stall.

So, what I did was do this a couple of times, then applied the gas for a few seconds, and the engine actually idled (but at 500, 750, and later 1k as the day progressed).

From this, I'd say something is clogged and my first reaction would be injectors - any fast way to check it?

My instructor at school thought it would be a TPS gone bad.

Here are my error codes you may find useful since we share the same problem:

12 Speed reference pulse
16 System volts too high (not sure whats up with this, ignore it)
22 TPS volts too low
25 MAT temp too high
31 P/N switch faulty
32 EGR failure
34 MAP voltage faulty
41 Cam sensor/cylinder select error
42 EST

So, I'm gonna go try to figure this one out, I'll see what I can find.

85Iroc-Z

iTrader: (4)

Mine stalls when i give it gas though.

85Iroc-Z

iTrader: (4)

How about a Fuel Pressure Regulator? Fuel Pump?

85Iroc-Z

iTrader: (4)

On another forum i was told an o2 sensor. Can this make the car stall?

stricnyne

I had this issue a few years ago and kept getting a code 34 after much headaches it turned out to be the IAC...fairly inexpensive. I have a similar but worse issue now with no trouble codes. Just cause you have a code indicating a particular sensor doesn't always mean it is that sensor. It could be a bad sensor inline that causes another sensor to set a code.

85Iroc-Z

iTrader: (4)

Should i take the IAC out and clean it or should i just buy a new one if it is dirty?

stricnyne

When you remove it you will see that it has a spring loaded tip. I can't remember the spec. but there is a spec for how far the tip should be extended. You could try cleaning it but for mine it didn't work...the spring usually gets so worn out the the IAC doesn't even function poperly anymore.

85Iroc-Z

iTrader: (4)

My car now doesnt start up and stall anymore. All it does is when its turning over is it sounds like it is gonna start but never does. Is there anything different that can cause this?

stricnyne

I don't have a clue...you are in the same boat as me now. I have been working on my car and testing things all night and now mine doesn't even sound like it is getting any spark. I think my ECM is f--ked cause even when I disconnect things I don't get any error codes. Have you disconnected your neg bat cable to reset the codes...if yes...are you still getting error codes when trying to start it?

77monte

The O2 sensor will have nothing to do with the starting problem. It will run while spraying carb cleaner in it though? Its completely possible for a fuel pump to pump out good volume with no pressure. That would explain the gas in the lines. But if it starts and runs on cleaner i would say the fuel pump is bad. Can you test the fuel pressure?

85Iroc-Z

iTrader: (4)

Yes, it does run on starting fluid. I will check the fuel pressure once i find a gauge that i can use. Is there any way to test if my pump is good without pulling it out once again?

85Iroc-Z

iTrader: (4)

How do you energize the fuel pump by using the diagnostic connector? I know you can stick a wire into two connectors of it, or use a paper clip but how should it be done?

stricnyne

hey fixed my car yesterday...since your problems are similar...have you checked you ignition module for corrosion...that was the problem in my car.

Cratemaster

My girfriend had the same thing happening to her car. It's a '97 dodge stratus, but it would run for a few seconds then die. It was because of a bad fuel pump. She would try to start it and it would eventually build up enough fuel pressure to start, but the pump couldn't sustain that pressure so it would stall. I would definately check the fuel pump.

85Iroc-Z

iTrader: (4)

I think it is probably the fuel pump also, because with the starting fluid in it, it will run until it is all burnt off. The only thing i cant understand is how it wouldnt start for about a month, then one day it started and ran perfect, but now it still doesnt start.

85Iroc-Z

iTrader: (4)

Can somebody describe in detail how i can run a jumper wire to the fuel pump relay to make the pump run for as long as i need it to in order to do a fuel flow test. Ive done it before but i dont exactly remember how. Im gonna try to make the pump run for 15 seconds to test how much fuel comes out and i figure i should do it this way since i was told that by turning the key on every now and then for the 2 seconds to add up to 15 seconds is not an accurate way to do it.

85Iroc-Z

iTrader: (4)

Anybody?

sqzbox

Apply 12 v to the bottom left slot on your ALDL connector under the dash. This should energize the fuel pump. With a fuel pressure gauge connected you will get a reading. Then check your fuel pressure specifications and that will tell you if your fuel pump is bad. 9 to 13 lbs. for TBI and 34 to47 for MPFI.

85Iroc-Z

iTrader: (4)

This is probably a very stupid question, but how do i apply the 12volts to the ALDL in terminal G(bottom left corner)?

sqzbox

I use a continuity tester. find a hot connector on your fuse block and attach the alligator clip and poke the end of the tester probe to term. G.


F E D C B A
_ _ _ _ _ _
_ _ _ _ _ _
G H J K L M
X

Bigwavedave

Had this happen on an old Honda - The ignition switch went bad - Engine cranks okay, but when release key to run position, it would shut off. It started doing it for a while where I could restart and it was okay, but eventually died.

I ran a jumper on the wires for run and started it okay. Try a jumper wire and see if it works (essentially hot wire the car). Not sure if you need extra steps with VATS.

Another problem I had (can't fully remember the symptoms) was the temp sensor going bad - made the engine run extremely rough - on startup I had to keep the throttle on. I noticed it go out when I overheated (fans stopped running). Got home by revving it high at stops.

85Iroc-Z

iTrader: (4)

How do i just jump the FP relay then? I remember in the past doing it somehow by sticking an end of a wire into one part of the FP relay and stickin the other end of the same wire into the FP. Can any describe to me how this way can be done?

85Iroc-Z

iTrader: (4)

Can i just take a 16 gauge wire, splice the 2 ends, stick them in the furthest left and right connectors, and turn the key forward?

85Iroc-Z

iTrader: (4)

85Iroc-Z

iTrader: (4)

Ok i just did my fuel flow test finally. I read in my Hayne's repair manual that the fuel pump should supply 1/2 pint or more in 15 seconds. When i did the test i was over a 1/2 pint within 2 or 3 seconds. Is there something wrong with my car with it giving this much gas, or is the 1/2 pint measurement wrong?

85Iroc-Z

iTrader: (4)

As i said the fuel flow test showed i am getting plenty of fuel at the fuel supply line. What is another possibility, my injectors? When i attempt to start it, all it does is it sounds like it while fire up but never does. Any ideas?

85Iroc-Z

iTrader: (4)

What is the difference between the oil pressure/fuel pump switch behind the distributor, and the oil pressure/fuel pump switch that goes into the block above the oil filter?

85Iroc-Z

iTrader: (4)

Is it a possibility that my injectors might not be letting any fuel through them? Also anybody know about the oil pressure fuel pump switch question in the previous post?

z 28 jari

iTrader: (1)

Oilpressure sending unit behind distributor is for gauge,and another gives "backup" supply voltage to fuelpump if fuelpump relay fails.

85Iroc-Z

iTrader: (4)

How can i check to make sure my injectors are working properly? I know that i have good fuel flow to the motor and im guessing the only thing left i have to go from there is the injectors, the fuel pressure or the oil pressure fuel pump switch.

85Iroc-Z

iTrader: (4)

Alright. the problem has to be my injectors. It runs when i use starting fluid, but when i dont use it, it wont run. After trying to get it to run without the starting fluid, i took the plugs out and they were dry. So i checked to see if the fuel was gettting to the motor. Took the fuel line off and let the pump run and it pumped plenty of fuel through. So what should i look into with the injectors?

85Iroc-Z

iTrader: (4)

A ground wire, solenoid, relay?

Viprklr

iTrader: (5)

You need to get the "tools" required to do the tests that have already been mentioned. You're trying to fly in the dark here.

Just because you're pump puked out more than 1/2 pint doesn't mean the pressure's good. CHECK your fuel pressure.

Don't worry about the oil pressure/fuel pump switch. It's only a back-up.

Tool's to check your codes........an unbent paperclip stuck in both A and B terminals that sqzbox posted. Count flashes of the SES light.