Geechy

Hello fellow GS stuntmen. I was trying to find answers to my problems throughout the forum but to no avail so I may be asking questions that may have been resolved one way or another. The problem is noone is posting their resolutions if they find a fix for it; at least for my problem.

I have a 94 GS300 189,000 mi that runs for a few minutes after it sits for a few days. When it shuts down it'll spin over but won't start. The fuel pump runs, I've checked the fuel ECU and its good (bypassed it and car still wont crank), i've verified that its getting fire (spark), and i've changed ignition coil and igniter. Also the injectors are making a clicking sound when I turn the ignition to the ON position. When it does start, it seems to be shutting down once it warms up. I saw a post about the coolant temp sensor in which someone said that when he changed his out, the car ran like new. Would a faulty coolant sensor cause the car to shut down once it gets warmed up or is my ECU a more likely culprit? How can I test the coolant temp sensor or ECU? Thanks for your help.

Yakshii

iTrader: (1)

it could be SOO many things. its hard to determine exactly what it is and pinpoint the problem while just reading a post. Tow it to a trusted mechanic.

kene

iTrader: (2)

Have you tried to pull any Check engine Codes? Even if the check engine light does not come on, there can still be underlying codes.

Geechy

Thanks for replying. I've tried pulling codes but the CEL just flashes on and on. I put an ECM on it yesterday and it does the same thing. Runs for about 5 min or so and shuts down once it gets warmed up. I took out the fuel pump and checked the strainer and the tank for trash but its clean. Forgot to mention that it gradually dies and doesn't just shut right off. You can hear the engine fade away before it cuts off. I was told that that is a symptom of a faulty catalytic converter. Trying a set of plugs next but I'm kind of on the fences about that. Any suggestions?

kene

iTrader: (2)

ok.. if there is no check engine light the ECU thinks everything is fine.(provided its not faulty)

If you are wondering if it is the ECU, you can open it and check. With it open look o see any signs of leaking, or bloated/bulging capacitors(check google.com to find out what capacitors are and how they look when bloated or leaking). If you do see bloated/bulging/leaking capacitors they can be replaced with a capacitor of the same type and capacitance.

http://www.engineeringslash.com/wp-c...capacitors.jpg



if it is a faulty catalyt conv. ask a muffler shop to do their evaluation for a few bucks. might be worth the headache letting them deal with it versus you.(if you have snow in your area the bolts may be rusted tight.)

Option 1:
dang, it might have been best to hook it up to a car battery, get a little bit of hose, and create a mock setup simulating the pump's operation for a given amount of time. If its not too much to get it out again this may be the best option. you can let the pump cycle water instead of fuel as it is safer. And then when the test is done, remove the water and add some fuel to flush any water out of the pump.

Option 2(recommend option 1):
To check for a gradually dying fuel pump(on the car...CAUTION: DO AT YOUR OWN RISK... THIS CAN BE VERY DANGEROUS IF YOU DONT KNOW WHAT YOU ARE DOING. ALL IT TAKES IS A STATIC ELECTRIC SHOCK TO IGNITE FUEL).
-Have fire extinguisher handy, and test it before you begin
-with my older cars I would take off the distributor cap(or unplug all spark plug wires from the distr. cap) and then remove the fuel line(take the "Banjo bolt?" off) from the fuel rail and point the line to an empty non-conductive bucket.

I then would turn the key to the on position(last position before the engine cranks over...don't crank it over). This sends power to the fuel pump and lets it pump fuel into the non-conductive rubber bucket verifying how well it works. for your case you may need to do this a few times as the bucket would fill up before you reached your "5 minute engine shut off problem".


If you still are unsure if it is the fuel pump or not and still want to further check, I'd recommend option 1 vs option 2. Much safer.

Geechy

The ECU I pulled from the car had two leaking caps so I located a shop that has a few. I originally was going to buy a used one from him but when I got there the guy said that he would replace the caps and clear the cicuitry paths for $100 and warranty the wrk so I jumped on that. I didnt open it back up to see what/ if he did. Being that the car is behaving the same as before, I'm assuming the problem is elsewhere. But same ECU same problem..hmmm. I'll try your suggestions first Kene, before I throw the ECU thru that shop window. I'll update shortly. Thank you

kene

iTrader: (2)

10 char
no prob.

Geechy

Got her fixed!! It was the darn fuel pump. The mechanic said that the ECU was going bad which caused the fuel pump to start failing. Kene I was going to try your troubleshooting methods but I just got fed up with it and decided to let him deal with it. Mechanic got it running that evening.

kene

iTrader: (2)

Glad to hear. thanks for the update. I'm sure that this information will help the net guy in the future.