it would appear that I'm not getting fuel out the injectors |
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it would appear that I'm not getting fuel out the injectors |
Downerman |
Apr 26 2019, 03:17 PM
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#1
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
Can't make an injector squirt. Was trying the cold start valve and then read where it had to be cold...like real cold for California as it in the high 80's today and I see it's also connected to a temp sensor so it's no wonder why that was not squirting on start. I was thinking of it as a prime of sorts for a engine cold start.
Anyway I digress. The overall problem is I crank and nothing. I smell some fuel but no leaks. Ignition was testing using Pelican parts protocol and it all checked out. As soon as the wife get's back I will actually pull a plug and see for myself at the plug but it would seem all is well there so I'm looking at fuel. MPS ohm'd out and has tangerines new diaphragm in it. I pulled an injector and checked voltage at the 2 wire plug with the starter blazing away and I got minimal voltage. I believe it was under a volt. What should that be? Can I check the injector by applying a 12V supply to the two pins? It ohm'd out at 2.5 For the record, I primed the fuel system my applying 12V to the pump for a minute. I'm at 31 not 28 based on others who have a slightly larger displacement and that's spot on. My old problem of no 1.5 burst of the fuel pump has been fixed with another ECU. So, when that 1.5 second burst happens does it also open the injectors and prime the cylinders? So close and yet so far. Dave |
jcd914 |
Apr 26 2019, 03:26 PM
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#2
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
There is no "prime" for the injectors.
As you crank the engine the FI points in the distributor open and close signalling the FI control unit to pulse the injectors in pairs. I am not sure you can test injector operation with a voltmeter because it is a pulse no a stead voltage. Get a "noid" light at FLAPS and plug it into an injector plug and watch for it to flash while you crank the engine. At least you are moving forward and working through the issue. Good luck Jim |
JeffBowlsby |
Apr 26 2019, 04:19 PM
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#3
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914 Wiring Harnesses Group: Members Posts: 8,513 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
2.3v is all that’s needed. More and you’ll fry it. Tap it momentarily to a 9v battery works to test, but don’t hold it at that voltage. Send the injectors out for cleaning and testing? They get corroded or gummed up if they sit awhile.
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Downerman |
Apr 26 2019, 06:03 PM
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#4
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
2.3v is all that’s needed. More and you’ll fry it. Tap it momentarily to a 9v battery works to test, but don’t hold it at that voltage. Send the injectors out for cleaning and testing? They get corroded or gummed up if they sit awhile. Huh... so I just tested a 9 volt last week and it was like 4.1 volts. I still had it and pulled the injector and hose off the rail. Benched it and tapped the 4.1 volts. NADA. It does Ohm at 2.5 but I'm guessing it's like Jeff says and is gummed up solid. This car sat in a industrial area in Van Nuys for years basically a shell and all the parts in multiple boxes. No wonder. So I could have other issues but this certainly explains why I don't have it running. I did get my wife to hit the key/starter and I have a nice spark on the plug to the tin. So are there NOS injectors or is it better to just but rebuilt ones. I have no clue as to the mileage on this car. The engine and trans are rebuilt...yeah shame on me for using thee old injectors but they look decent but I do know that they wear and I certainly cannot spray a pattern to see so I'm just going to take the plunge. Any recommendations? Dave |
rhodyguy |
Apr 26 2019, 07:14 PM
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#5
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,082 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
witchhunter.com. $22 each for refurbish. People seem to like their work.
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r_towle |
Apr 26 2019, 07:46 PM
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#6
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Custom Member Group: Members Posts: 24,579 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
You can try and dunk them in fuel injectors cleaner that you buy for pouring into the tank for a few days, but they probably need an overhaul after 40+ years.
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bdstone914 |
Apr 27 2019, 09:02 AM
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#7
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bdstone914 Group: Members Posts: 4,524 Joined: 8-November 03 From: Riverside CA Member No.: 1,319 |
You state you have no fuel out if the injectors.
So..... 1. Check fuel pressure at the port on the fuel rail. 2. Use Noid lights to check for electrical signal at the injector plug. Start with basics. Fuel and signal. If there is no signal could be the trigger points. Injectors fire in pairs. |
rhodyguy |
Apr 27 2019, 09:05 AM
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#8
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,082 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
Is the intank screen sucked flat?
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Downerman |
Apr 27 2019, 09:38 AM
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#9
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
As mentioned.... 31 PSI on rail. Don't have a noid light but do get small doses of voltage at injectors. Screen in tank is brand new. I have fuel and great circulation in the system itself. Found one injector working sort of.
For ducks I'm going to try the Ammonia based window cleaner in my sonic cleaner unit for 30 minutes and then test with 9 volt that is actually 4.5 Ultimately will go the route mentioned above for the rebuild units. Basics are good. It's either fuel or fire and I have fire. thanks for all the posts. I will give an update hopefully positive. Dave |
Superhawk996 |
Apr 27 2019, 11:21 AM
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#10
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914 Guru Group: Members Posts: 5,852 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Just received 4 injectors back from Mr. Injector out of Dalton Gardens Idaho. Sent 7 of which I knew 2 were probably hopeless.
$17.50 per injector for ultrasonic cleaning, new micro screen, new pintle cap, new seals, and nicely repainted. Plus he added new stub hoses and proper FI hose clamps that I wan't even expecting. Flow tested before and after for both flow and pattern. I received 4 back with identical flow and confirmation of good pattern. He only charges the $17.50 per injector for the ones that are serviced. 3 duds were returned to me with no charge associated with them. I'll probably just cut those open for fun & education. |
Spoke |
Apr 27 2019, 01:00 PM
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#11
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Jerry Group: Members Posts: 6,984 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
I pulled an injector and checked voltage at the 2 wire plug with the starter blazing away and I got minimal voltage. I believe it was under a volt. What should that be? As mentioned previously, the voltage to the injector is a pulse so a voltmeter reading DC volts will average the voltage it reads. Back to calculus class, a pulse averaged out over the period will be: VDC = Vpulse * TON/TOFF. Vpulse = 12V and time on (TON) is like 10ms. Time off (TOFF) is like 100ms which is the rotating of the engine. So you should expect to measure VDC = 12 * 10/100 = 1.2V. Your measurement is not that far off. To check injectors, pull an injector and place it in a jar and crank the engine. You should see squirts happening. To check that it's fuel, spray some starting fluid in the intake. If the engine fires then dies, it's fuel. If the engine doesn't fire, it's spark. |
worn |
Apr 27 2019, 01:30 PM
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#12
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can't remember Group: Members Posts: 3,156 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
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Also. At a quiet time, turn the key to ignition on. Then slowly press the gas pedal to the floor. As I recall, you should hear 5 injector clicks. I got that one from the Hussey 700 tips book. A good source for a lot of things 914. |
Chi-town |
Apr 27 2019, 03:55 PM
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#13
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Senior Member Group: Members Posts: 850 Joined: 31-August 18 From: Disneyland Member No.: 22,446 Region Association: Southern California |
Most volt meters are not fast enough to display injector driver voltage properly. Use a noid light (available at harbor freight) and see if it flashes.
Check for fuel pressure Check for ecu power |
Downerman |
Apr 28 2019, 10:47 AM
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#14
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
Again, great info and I appreciate it. So yesterday started good. Pulled all the injectors and cold start that would not do squat with a quick 9 Volt. Used Windex with ammonia and my sonic bath cleaner and after about 30 minutes they were all working except one that took another 30 minutes.
Thought that was going to be it.... Nope. So found TDC and checked pug wires, timing and while I was at it... .checked the valves. Weird stuff Maynard..... ALL the exhaust valves were way off. Had to back them off considerably. Intakes were pretty close. That's 006 on intake and 008 on exhaust. Has me kind of freaked out thinking I wore the cam lobes just working through the original ECU problem and now this but the intakes were good. So today I'm going to pull the injectors and place them in small plastic containers and see how they perform in the car and not on the bench. Second thing is I'm going to do a compression check on all four cylinders. Dave |
Superhawk996 |
Apr 28 2019, 10:54 AM
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#15
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914 Guru Group: Members Posts: 5,852 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
If you are absolutely sure you checked engine dead cold and you had the cylinder exact TDC, and the exhaust valves were tight (i.e. you backed them off), this is an early warning sign.
Valve stem is stretching. Next occurrence in the sequence is that the valve head breaks off and destroy's your engine. Double check that you adjusted properly. Keep a very close eye on valve adjustment. If the exhaust valve gets tight again . . . rebuild the heads before engine failure occurs. |
Downerman |
Apr 28 2019, 12:10 PM
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#16
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
If you are absolutely sure you checked engine dead cold and you had the cylinder exact TDC, and the exhaust valves were tight (i.e. you backed them off), this is an early warning sign. Valve stem is stretching. Next occurrence in the sequence is that the valve head breaks off and destroy's your engine. Double check that you adjusted properly. Keep a very close eye on valve adjustment. If the exhaust valve gets tight again . . . rebuild the heads before engine failure occurs. Interesting.... The engine is rebuilt but never has fired up. The heads are completely rebuilt. Like I said.... never even a bad fire up. I'm wondering if I went clockwise on the fan like my 911 not even thinking but that wouldn't explain why the intakes were decent. I don't know... compression check and injector test after the honey do list is done. |
Superhawk996 |
Apr 28 2019, 01:04 PM
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#17
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914 Guru Group: Members Posts: 5,852 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
If engine was rebuilt and never run then the scenario where they were mis-adjusted at assembly is reasonable.
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Downerman |
Apr 28 2019, 01:50 PM
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#18
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
If engine was rebuilt and never run then the scenario where they were mis-adjusted at assembly is reasonable. LOL that would be me!! and I take full responsibility. I think my senior moments are getting serious. So I have: Cylinder 1, 135Lbs Holds pressure Cylinder 2, 125Lbs Holds Pressure Cylinder 3, 140 Lbs Holds Pressure Cylinder 4, 140 Lbs Holds Pressure. The rings haven't even been seated. I also have fuel at each injector. I have spark when cranked, plug/wire to tin. Cylinder 2.....will check them all after lunch when wife get's back. |
Downerman |
Apr 28 2019, 01:54 PM
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#19
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
If engine was rebuilt and never run then the scenario where they were mis-adjusted at assembly is reasonable. LOL that would be me!! and I take full responsibility. I think my senior moments are getting serious. So I have: Cylinder 1, 135Lbs Holds pressure Cylinder 2, 125Lbs Holds Pressure Cylinder 3, 140 Lbs Holds Pressure Cylinder 4, 140 Lbs Holds Pressure. The rings haven't even been seated. Also wondering about my fuel. I put 91 Octane in the tank before Christmas thinking I would be getting the engine in and firing it up. Shit happens and it's been 5 months. But I DO have fuel at each injector. I have spark when cranked, plug/wire to tin. Cylinder 2.....will check them all after lunch when wife get's back. |
Spoke |
Apr 28 2019, 01:56 PM
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#20
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Jerry Group: Members Posts: 6,984 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
If you have spark, then the engine should fire. Try spraying some starting fluid into the intake and see if the engine briefly fires up.
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