90 - starting / no starting problem
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Joined: Jan 2007
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From: Cumberland Rhode Island
90 - starting / no starting problem
Hi, I have a 1990, 106,000 miles, L98 (I think) with a 6 speed. The problem I am having is when it is hot out the car will not start. If we spray starting fluid down the plenum it will start right up and continue to run with the fluid and then stalls without the fluid. This happens when the engine itself is cold from sitting over night etc. go out on a cooler day and the car will start up and run with no problems at all. For example, the other morning, I needed to get by the car so I started it up and moved it about 20 feet. The car started right with no issues. Later on that same day, I tried to start it will no luck. One shot of starting fluid and it starts and runs until the fluid runs out. Obviously this is a fuel problem but I have no idea where to start. Yesturday, I started it up and took it for a ride again with no issues. Even when the engine is hot it starts right up. Seems to be only when it is very hot outside for some reason but that could be just a coincedence. Lastly, yes there is fuel in the tank. The gauge says 1/2 tank and I put in an extra 5 gallons just in case the gauge was wrong. Also all fuses look to be in good shape with none blown..... 
thanks for your help!
thanks for your help!
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Joined: Apr 2007
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From: Greenville SC
I also have a 90 model that used to give me issues starting, especially if the motor was hot. It turned out that the injectors were toast. I replaced them with FIC bosch III and it now starts like a new car no matter the conditions every time. I would also check your fuel pressure as well.
Le Mans Master
Joined: Jul 2007
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From: Tampa Florida
I also have a 90 model that used to give me issues starting, especially if the motor was hot. It turned out that the injectors were toast. I replaced them with FIC bosch III and it now starts like a new car no matter the conditions every time. I would also check your fuel pressure as well.
Order some new injectors the stock ones are falty from the factory.... Bosh has a better spray atomization... Check FIC thread for sale info and a great demo of this common type of multec failure.
Good Luck!
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From: Cumming Ga
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Joined: Jan 2007
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From: Cumberland Rhode Island
I measured all of the injectors with the engine cold. I also put in new bateries in my ohm meter just in case. The car has sat for a long time in between driving....
Cyl 1 = .016
Cyl 2 = .016
Cyl 3 = .016
Cyl 4 = .017
Cyl 5 = .016
Cyl 6 = .016
Cyl 7 = .016
Cyl 8 = .017
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
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From: Cumming Ga
Thanks FICINJECTORS for your PM and the link on how to check injectors.
I measured all of the injectors with the engine cold. I also put in new bateries in my ohm meter just in case. The car has sat for a long time in between driving....
Cyl 1 = .016
Cyl 2 = .016
Cyl 3 = .016
Cyl 4 = .017
Cyl 5 = .016
Cyl 6 = .016
Cyl 7 = .016
Cyl 8 = .017
I measured all of the injectors with the engine cold. I also put in new bateries in my ohm meter just in case. The car has sat for a long time in between driving....
Cyl 1 = .016
Cyl 2 = .016
Cyl 3 = .016
Cyl 4 = .017
Cyl 5 = .016
Cyl 6 = .016
Cyl 7 = .016
Cyl 8 = .017
Thread Starter
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Joined: Jan 2007
Posts: 90
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From: Cumberland Rhode Island
Well here it is a year + later and I am finally getting back to work on the 90. I tried starting it today with no luck at all. It turned over fine with no issues there but just would not start. To me it sounded like I wasn't getting any fuel and/or spark. When I checked the injectors a while back all the coils were in the .016/.017 range. I did not check today as I was by myself but last time it had great spark also. Still sounds like a fuel problem to me??? Any idea where or what I should check next? If you read my first post in this thread you will see how it was acting up prior to being stored.
Thanks!!
Thanks!!
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Instructor
Joined: Mar 2006
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From: Stockbridge GA
Change the injectors. My 90 had similar issue but my injectors were all bad. Changed the injectors and problem was gone. On top of that I picked up a little better milage. Go ahead and get them from Jon. You will not be sorry.
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
Buy a fuel pressure gauge (about $12) and connect it to the shrader valve on the right side fuel rail. Turn the ign on for longer than 2 seconds and turn it off. You should get 35-42 psi and it should hold up for a long time. If you lose pressure rapidly, you likely have one or more injectors that are leaking. Also, while everyone has an ohmeter, ohmeters only make a d.c. (direct current) test of the injector coil and injectors receive pulses from the ECM and a much more sensitive test for injector coils is to measure their a.c. (alternating current) impedance. An ohmeter cannot find a coil with a turn to turn short (the change in resistance is microscopic), and this defect will not allow the injector to work, BUT...an impedance bridge will find this kind of defect instantly!
FIC injectors is in the business of testing and selling injectors and I would recommend that you listen to his advice and take advantage of his experience.
Also, your injector coils should measure around 16 ohms, not .016 ohms.
FIC injectors is in the business of testing and selling injectors and I would recommend that you listen to his advice and take advantage of his experience.
Also, your injector coils should measure around 16 ohms, not .016 ohms.
Last edited by jfb; Apr 14, 2010 at 12:08 AM.
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Joined: Jan 2007
Posts: 90
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From: Cumberland Rhode Island
Update....
It has finally stopped raining so I went out today and tried a bunch of the tips people have given me. I applied 12V power to the "G" terminal on the ALDL and nothing. I checked and replaced the fuse and also switched out the relay with one of the other three that were under the dash and still nothing. When I run 12V directly to the pump the car starts perfectly. I am not even sure where to start chasing the wires in this car are there are a million of them!!
It has finally stopped raining so I went out today and tried a bunch of the tips people have given me. I applied 12V power to the "G" terminal on the ALDL and nothing. I checked and replaced the fuse and also switched out the relay with one of the other three that were under the dash and still nothing. When I run 12V directly to the pump the car starts perfectly. I am not even sure where to start chasing the wires in this car are there are a million of them!!
Team Owner
Joined: Jan 2003
Posts: 20,323
Likes: 249
From: Summerland B.C. Canada
Do you have the 90 FSM ?
There are 2 sources of power for fuel pump, the fuel pump relay and an oil pressure switch. The oil pressure switch should apply power to pump at about 4 psi, so cranking should trip the switch. Maybe you have a blown fusible link that feeds the relay and switch, or some bad wiring/connection.
There are 2 sources of power for fuel pump, the fuel pump relay and an oil pressure switch. The oil pressure switch should apply power to pump at about 4 psi, so cranking should trip the switch. Maybe you have a blown fusible link that feeds the relay and switch, or some bad wiring/connection.
Thread Starter
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Joined: Jan 2007
Posts: 90
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From: Cumberland Rhode Island
Not sure what 90 FSM means....
I replaced a fuse that was under the passenger dash labeled fuel2 or something like that and I also found a power fuseable link wire coming off some relay or block behind the battery that had been poorly spliced together. I cut out the bad splice and reconnected the wires together and now the car is starting right up. Running a little poorly now but it is possible that i knocked off a wire somewhere... will check for that soon.
I replaced a fuse that was under the passenger dash labeled fuel2 or something like that and I also found a power fuseable link wire coming off some relay or block behind the battery that had been poorly spliced together. I cut out the bad splice and reconnected the wires together and now the car is starting right up. Running a little poorly now but it is possible that i knocked off a wire somewhere... will check for that soon.
