Tech / General EngineWhy is my car making that sound? My car won't start! Combination questions? Don't see a board for your problem or have other technical or engine specific questions? Post them here!
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Here is the problem: 1989 IROC 350 TPI, the car does not want to start cold.
Sometimes it will start after cranking for a long time, sometimes not. If you shoot some propane into the intake it fires up and runs. Runs fine after it starts until you shut it off then sometimes it fires right up, sometimes you have to sit and crank it.
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Last edited by bowtiesandbirds; 08-07-2008 at 03:32 PM.
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My fiancee was stuck in Florida with the car and had it to three different shops. The fuel pump, pump reley & oil pressure switch have been replaced.
The injectors have been removed cleaned and checked. I replaced the fuel filter just to eleminate that. I checked the spark, seems to be good. I unhooked the fuel lines at the engine and fuel is flowing threw the system.
I don't have a guage to check the pressure though. The regulator seems like the only major part left. I'm sure the shops would have checked that though.
IAC is the idle air control valve. It is on the bottom of the throttle body and acts like a choke on the car. It closes on start up and then opens back up when the car idles. If the car idles fine then this probably isn't the issue. Checking fuel pressure is a very good start.
__________________ Todd
Black 89 IROC 5.7L
Random Technologies catback
Edelbrock TES headers
MSD igntion
3.70 9 bolt
Run a test on the IAC vave and also check the TPS voltage. They have a good tech article on how to do this right here on this site. http://www.thirdgen.org/tpimod2
__________________ Todd
Black 89 IROC 5.7L
Random Technologies catback
Edelbrock TES headers
MSD igntion
3.70 9 bolt
I checked the fuel pressure valve by just pushing it in. When the car is running it squirts out pretty good. When I check it with just the key on after the pump primes and stops it just dribbles out.
Is that normal or part of the problem?
The IAC article just shows how to adjust it at idle. The car ides fine once it is started.
I am new here to and have the same problem but a 1987 350 but only at hot.
I did not replace any of the above that you mentioned but I have several thoughts as to what it could be.
Because I am married I can't spend any money on it but here are some things.
The not holding pressure when the key is off is usally due to the pulsator in the fuel tank which holds the pressure on the return line. Did they replaced the Pump, filter or (sock) in the tank and the pulsator?
Another common problem with these cars is EGR valve as well. This is located under the plemuim.
Also a common issue is the reluctor in the distributor and the pickup coil in the distributor.
The fuel pump was just replaced but I was not there to see what they did or did not replace other than that.
It is getting spark but there could be some other issue with the distributer on startup.
That the weird thing, once it starts it is fine and can be driven forever until you shut it off. Then if you are lucky it starts again if not you just sit there and crank it.
When it does start. You crank for awhile and it will hit a little here and there.
It just starts hitting more and more until the car finally starts.
My car does the exact same thing. I just do I quick crack of the starter and it usally works the best.
They should replace everything when they are in there. When running my pressure is at a 43.5 adjustable pressure for my injectors but you should get a pressure gauge on the fuel rail to see if it is holding at all. My has been diagnosed as a pulsator problem but when I get the money I will change all of the fuel pump system.
On my car I am going to change the distributor first it is easier and my car has 120,000 mile on it so it is due.
I just looked through the bag of parts the mechanic gave my fiancee after they did the "work".
Fuel pump & sock. No pulsator. I'll bet that is it. It is the only thing that really makes sence. All the mechanics thought the fuel pressure was bleeding off but didn't know why.
Last edited by bowtiesandbirds; 08-12-2008 at 12:48 PM.
I have a shop manual at home if I can I will scan the procedure for you but you really need a pressure gauge.
I can only go by memory at this point but the procedure is to connect fuel pressure gauge. Turn ignition key on pressure should read 40.5-47 PSI and hold. If not holding turn the key off pinch with vise grips the inlet fuel line hoses rubber flex line located near the brake master cylinder. The inlet is the larger one looking at the front of the fuel rail and follow to the flex hoses pinch off and turn the key on if pressure holds then there is a problem with the Fuel Pump, Pulsator or fuel pump pressure valve. If pressure falls then it is one of the injectors or fuel pressure regulator. Next pinch off the return line if pressure holds then it is definatly the pulsator.
I will verify tommorow with my shop manual. But I am pretty sure this is the procedure.
Daryl
Last edited by dmanella; 08-14-2008 at 10:08 AM.
Reason: Incorrect info in red will edit per service manual
I don't have a gauge and can't really afford to buy one right now. I will see if I can get ahold of one though.
The injectors have been cleaned and checked so they should be working. So it sounds like that would leave the regulator or pulsator as the most likely faults.
Bowtie I am having the same problem. Car runs fine after starting, but it wont start unless I spray a little starting fluid into it. A few months ago the problem was hit and miss but now it's everytime I try to start it. Has anybody found the problem yet?
The car runs like a gem after I get it started. But most the time, if I shut it off, I am back to the starting fluid. And It dont matter if the engine is warm or cold still the same. Fuel pressure is holding for a few minutes before it starts to bleed down so I dont think fuel is the problem.
How much doe's the pressure drop and how long does it take. If you turn the key on and have the pump come on the pressure should stay between 40.5 and 47 PSI if it drops any more than this then follow the steps above I just did it on my car and it is definatly something in the fuel tank for my car.
If you crank and crank and crank the car will never start. Just turn the key on you will here the fuel pump relay click on which will prime the injectors. Turn the key just quick hit don't hold it. Keep doing this and it may take three to five trys but it is better than pulling out the starting fluid and spraying it in there I have been doing this for several weeks now and have not had to use the starter fluid once since I started doing this.
How much doe's the pressure drop and how long does it take. If you turn the key on and have the pump come on the pressure should stay between 40.5 and 47 PSI if it drops any more than this then follow the steps above I just did it on my car and it is definatly something in the fuel tank for my car.
If you crank and crank and crank the car will never start. Just turn the key on you will here the fuel pump relay click on which will prime the injectors. Turn the key just quick hit don't hold it. Keep doing this and it may take three to five trys but it is better than pulling out the starting fluid and spraying it in there I have been doing this for several weeks now and have not had to use the starter fluid once since I started doing this.
Daryl
I have solve this problem with hard start hot and cold. I replaced the distributor.
Hey guys im haveing a similar problem...
I have a 1990 iroc z 350
When i go to work in the morning it always takes me about 7 trys to get the camaro to start up i ususally let the fuel pump prime with my foot on the gas it seems to help it start. When the car heats up it runs great and fires right up. But after it cools down it starts all over again. I can smell fuel every once and awhile too. I dont know how to really check for anything either. I just bought the car. The owner said the fuel injectors run hot pn the car idk what exactly that means? Please someone help! Also when i brake to a stop i hear a banging noise er maybe a back fire? Also twise when i started it up i pressed down the pedal to the floor and had no power and went nowhere then the iroc died. HELP!~!~~!!!!
