problem with my 1975 2.0 d-jet running fine then died, it was running great and then... |
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problem with my 1975 2.0 d-jet running fine then died, it was running great and then... |
buck toenges |
Jun 30 2022, 06:09 PM
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#1
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Senior Member Group: Members Posts: 553 Joined: 25-November 03 From: Fort wayne In Member No.: 1,388 Region Association: None |
I have a 75 2.0 d-jet. i turn the key about 4 times to get the fuel pump sending gas to the engine. Starts right up. it idles a little low to begin with but then idles about 1000 rpm after 5min. So I decided to take a drive. running great down the highway no issues what so ever. After about 25 miles up the road engine dies. Battery is fine and the starter works well, not a battery issue. I can't restart it. Had to have it towed back home. Let engine cool down but still won't start. Fuel pump engages but no start. Shot some starting fluid in throttle body but again no start.
I know my fuel injection harness is not the best but it wasn't good before today. Looking on line I think it might be a cht sensor issue. Saw this online https://www.youtube.com/watch?v=fbmanDTIun8 They tested the cht to ecu and found out it was a bad cht. Once they changed it their car fired right up. I haven't checked the fuel pressure, I haven't checked the injectors, I did check spark and I have it on the sparkplugs. I shot some starting fluid in the spark plug hole and no start. Any ideas? It is funny that it was running great and then died. Buck |
GregAmy |
Jun 30 2022, 06:17 PM
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#2
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Advanced Member Group: Members Posts: 2,285 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
Same exact prob on my 74 2L turned out to be either a bad relay plate, bad relay, and/or bad connections between relay plate, relay, and/or wiring harness.
Remove all the connections, clean them up, lube with dielectric grease, and slightly spread the split-pin connectors on everything (relays and terminal pins. http://www.914world.com/bbs2/index.php?showtopic=304863 http://www.914world.com/bbs2/index.php?showtopic=310041 http://www.914world.com/bbs2/index.php?sho...&st=0&# |
emerygt350 |
Jun 30 2022, 07:56 PM
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#3
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Advanced Member Group: Members Posts: 2,087 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
It is a hair troubling that you say you have spark but with starter fluid it won't start. Does it kick over but just doesn't keep running or is it no firing at all?
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emerygt350 |
Jun 30 2022, 07:57 PM
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#4
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Advanced Member Group: Members Posts: 2,087 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
I would spray the fluid in the throttle body, not the cylinder head. The pcv port on the air cleaner is quick access.
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Amphicar770 |
Jun 30 2022, 08:18 PM
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#5
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Senior Member Group: Members Posts: 1,188 Joined: 20-April 10 From: PA, USA Member No.: 11,639 Region Association: MidAtlantic Region |
A while back, mine did similar when wire to cht was loose.
You may have answered your own question. Bad harness can cause all sorts of issues. All it takes is a bump and you have a broken connection or a short. |
Dave_Darling |
Jul 1 2022, 03:22 AM
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#6
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914 Idiot Group: Members Posts: 14,982 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
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buck toenges |
Jul 5 2022, 12:19 PM
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#7
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Senior Member Group: Members Posts: 553 Joined: 25-November 03 From: Fort wayne In Member No.: 1,388 Region Association: None |
Latest on my dead engine problem.
I went and cleaned the relay board connectors and added di-electrical grease. Nothing changed. I do have spark and fuel. I took off a injector and it sprayed fuel into a container. I do have spark on sparkplug. I can't get engine to fire with starter fluid. (if you have a bad cht could you still have engine start with starter fluid). I have tried to get reading on cht and can not get one. I hooked up my ohm meter with black to neg ground of battery and red to cht wire. I just took out cht from cylinder head. I placed black lead on the end that screws onto the cylinder head and the red wire on the cht wire to the fuel injection harness. I do not get a reading. I checked throttle position sensor and get clicks while I am moving throttle cable with ignition turned on. I did notice that when I turn over engine the suction on the throttle body is very weak. I was expecting more vacuum on my palm over the throttle body when cranking over engine. Stuck intake of exhaust valve? I did order a new fuel injection harness from Jeff Blowsby. Any ideas? Buck |
GregAmy |
Jul 5 2022, 12:27 PM
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#8
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Advanced Member Group: Members Posts: 2,285 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
Yeesh...spark and fuel and no fire...? That's ominous.
Next thing I'd do is compression test on all four. Pull valve covers and see if there's anything obvious. Get someone to turn the engine over with plugs out (and coil wire detached) while you watch it. I'll offer though that a sudden engine stopping to run without ugly bangy-bangy noises is rarely an indication of a mechanical problem. |
emerygt350 |
Jul 5 2022, 01:59 PM
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#9
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Advanced Member Group: Members Posts: 2,087 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Yeah, compression test first. Can't believe all cylinders died over night.
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emerygt350 |
Jul 5 2022, 02:02 PM
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#10
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Advanced Member Group: Members Posts: 2,087 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Is this car new to you by the way?
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buck toenges |
Jul 5 2022, 02:18 PM
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#11
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Senior Member Group: Members Posts: 553 Joined: 25-November 03 From: Fort wayne In Member No.: 1,388 Region Association: None |
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r_towle |
Jul 5 2022, 04:10 PM
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#12
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Custom Member Group: Members Posts: 24,573 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
AAR should create high idle when first started, then lower when warm.
I would suggest you check all vacuum lines to the plenum. You can unhook all vacuum lines, plug the plenum with electrical tape Leave just MPs hooked up Should start |
buck toenges |
Jul 5 2022, 04:47 PM
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#13
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Senior Member Group: Members Posts: 553 Joined: 25-November 03 From: Fort wayne In Member No.: 1,388 Region Association: None |
UPDATE
I uplugged the injectors and then sprayed some starter fluid in the throttle body. Engine started right up. Since my cht is shot that tells me I need a new cht in order to get the engine FI system to work again. The fuel injection system must have just richen the crap out of the a/f ratio because of a bad cht and thats why it won't start. Buck |
Olympic 914 |
Jul 5 2022, 05:03 PM
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#14
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Group: Members Posts: 1,662 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States |
You can wire in a resistor to mimic the cht.
Just to see if it starts then . |
brant |
Jul 5 2022, 05:38 PM
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#15
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914 Wizard Group: Members Posts: 11,620 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
I had a cht once that began working again when I pulled it to test
I think it lost its ground path |
GregAmy |
Jul 5 2022, 06:12 PM
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#16
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Advanced Member Group: Members Posts: 2,285 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
I uplugged the injectors and then sprayed some starter fluid in the throttle body. Engine started right up. That doesn't follow...unless a CHT prob is causing flooding...were you smelling raw gas before...? Paul Anders does state, "The CHT sensor (TS2), if disconnected or an open circuit, will not allow the car the start." However, he does not elaborate why. And if it's because of it not sending fuel to the injectors, then unplugging the injectors should have no effect on whether or not it will start with starter spray (no fuel from the injectors is no fuel from the injectors, no matter why). https://members.rennlist.com/pbanders/DJetParts.htm But keep going, you're getting closer... |
Dave_Darling |
Jul 5 2022, 07:41 PM
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#17
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914 Idiot Group: Members Posts: 14,982 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
If the CHT is unplugged, the FI sees that as Super Duper Ultra Cold and adds a ton of fuel. That's usually too much for the engine to start.
If the mixture is super duper rich, adding starter fluid (which acts kind of like fuel) won't help it to start. If you short the CHT lead to ground, does the car want to start then? --DD |
Spoke |
Jul 5 2022, 09:46 PM
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#18
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Jerry Group: Members Posts: 6,978 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
I placed black lead on the end that screws onto the cylinder head and the red wire on the cht wire to the fuel injection harness. I do not get a reading. I'm a bit late to your thread but when you say you 'do not get a reading', you mean you get infinite ohms, correct? An ohm meter will give you the ohms it measures, so if an open circuit, you're reading is infinite ohms. Sound like your CHT is bad. Infinite ohms on a CHT tells the FI that it should go super rich. Put a new CHT sender on and it should fire right up. |
emerygt350 |
Jul 6 2022, 06:19 AM
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#19
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Advanced Member Group: Members Posts: 2,087 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
But check to see if the old one is just having grounding issues first...
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buck toenges |
Jul 6 2022, 07:23 AM
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#20
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Senior Member Group: Members Posts: 553 Joined: 25-November 03 From: Fort wayne In Member No.: 1,388 Region Association: None |
If the CHT is unplugged, the FI sees that as Super Duper Ultra Cold and adds a ton of fuel. That's usually too much for the engine to start. If the mixture is super duper rich, adding starter fluid (which acts kind of like fuel) won't help it to start. If you short the CHT lead to ground, does the car want to start then? --DD I went out last night and ground out the FI lead to the cht wire. Shot some starting fluid in and the engine started right up. So the lesson is if your engine doesn't start and you think it might be the cht, disconnected the cht from the FI harness, ground out the cht lead and shoot some starting fluid into the throttle body. If engine starts than replace cht. |
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