 75 1.8 garage find won't start |
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| jhelgesen |
 Dec 12 2009, 08:42 PM
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Newbie  Group: Members Posts: 42 Joined: 14-July 08 From: Charlotte Member No.: 9,299 Region Association: None  |
(IMG:http://i184.photobucket.com/albums/x311/jhelgesen/75%20914/DSCN5132.jpg)
I'm trying to resurrect a 75 1.8 thats been sitting for 15 years. (she was hiding in a basement next to the furnace for all that time). Pretty darn rust free as far as 914's go. She got parked for FI issues. (IMG:http://i184.photobucket.com/albums/x311/jhelgesen/75%20914/DSCN5141.jpg) I'm trying to get her running again. I've got the tank clean. The fuel pump was cleaned and runs. The fuel injectors have been cleaned and checked, click well. Dual relay clicks when attempting to start. She turns over, but I'm not getting power to the fuel injectors. What to I try next? Thanks, |
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| jim912928 |
Dec 13 2009, 09:12 AM
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Senior Member Group: Members Posts: 1,487 Joined: 8-January 04 From: Granger, IN Member No.: 1,536 Region Association: Upper MidWest |
another key to the L-jet fuel injection is the Mass Air Flow sensor...this is the that large module that the air box bolts onto. If you take the top cover of the air box off you'll see a big flap that regulates the amount of air entering into the system. It opens up simply by the air being drawn into the system by the engine cranking/running. Key point is it is what triggers things like the fuel pump starting to run etc. If it sticks, power isn't sent to those (I'm guessing you are not hearing the fuel pump running also?). A few easy tests to do (on top of using the noid tool mentioned above):
1. spray a little bit of quick start into the air box...if the car runs for a little bit then you know you are getting spark and not fuel 2. crank the engine and manually push that air flap open on the MAF sensor...if it is sticking and the air doesn't have enough force to open it up on it's own...no power to fuel pump etc. If it starts you know what it is! BTW.....nice find! That car looks like it is in really great shape! |
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Posts in this topic
jhelgesen 75 1.8 garage find won't start Dec 12 2009, 08:42 PM
Mark Henry Your story is very much like my '74, with mine... Dec 13 2009, 04:50 AM type47 There is a tool called a "noid" that wil... Dec 13 2009, 06:56 AM
7275914911
There is a tool called a "noid" that wi... Dec 13 2009, 07:15 AM ClayPerrine
another key to the L-jet fuel injection is the Ma... Dec 13 2009, 10:21 AM stepuptotheMike :wavebye: Dec 13 2009, 10:46 AM davesprinkle Another thing to consider -- the Ljet brain requir... Dec 13 2009, 10:50 AM jhelgesen I have continuity to the resisters and they show a... Dec 13 2009, 11:16 AM jim912928 Clay...info I got was from a Porsche mechanic who ... Dec 13 2009, 12:24 PM jhelgesen Next step I'll check the coil and plugs.
When... Dec 13 2009, 12:52 PM type47 It should be easy enough to put an inductive timin... Dec 13 2009, 01:14 PM messix point gap/dwell? Dec 13 2009, 01:24 PM davesprinkle
point gap/dwell?
I agree. Sounds to me like yo... Dec 13 2009, 03:18 PM jd74914 I too am thinking you don't have a functioning... Dec 13 2009, 03:24 PM jhelgesen Timing light shows no spark....lets see what I can... Dec 13 2009, 03:32 PM jhelgesen Can't get power to the ignition. Jumpered a w... Dec 13 2009, 05:16 PM jhelgesen Put in new points tonight. I now have power at th... Dec 14 2009, 08:32 PM r_towle Back up. Pardon me if I am brief...
We need to ext... Dec 14 2009, 08:44 PM jhelgesen Good plan Rich, thanks, I'll start again. Dec 14 2009, 09:02 PM ahdoman Also check the 2 fuses on the relay panel. I belie... Dec 14 2009, 09:10 PM ClayPerrine
Clay...info I got was from a Porsche mechanic who... Dec 14 2009, 09:43 PM computers4kids
Clay...info I got was from a Porsche mechanic wh... Dec 14 2009, 10:26 PM ClayPerrine
[quote name='ClayPerrine' post='1250674' date='De... Dec 15 2009, 07:30 AM jhelgesen Does someone have this picture for a 75 1.8 car? ... Dec 15 2009, 06:38 AM type47 The factory workshop manual shows 3 relay boards, ... Dec 15 2009, 07:19 AM computers4kids My 74 Ljet has only has two relays and one does ru... Dec 15 2009, 08:42 AM ClayPerrine
My 74 Ljet has only has two relays and one does r... Dec 15 2009, 08:52 AM zonedoubt :agree:
To understand how the double relay works,... Dec 15 2009, 10:27 AM davesprinkle
You shouldn't need the fuse either. All of t... Dec 15 2009, 11:15 AM ClayPerrine
You shouldn't need the fuse either. All of ... Dec 15 2009, 02:42 PM Dave_Darling
My 74 Ljet has only has two relays and one does r... Dec 16 2009, 11:15 PM jhelgesen Super!
Thanks, Dec 15 2009, 10:51 AM jhelgesen Didn't make it past step one. No pump running... Dec 15 2009, 07:37 PM ClayPerrine
Didn't make it past step one. No pump runnin... Dec 15 2009, 09:54 PM r_towle you stated that the fuel pump runs when you run it... Dec 15 2009, 08:15 PM jhelgesen Tested power at the pump this morning. I got powe... Dec 16 2009, 06:39 AM jhelgesen Still trying to start the motor without success.
... Dec 18 2009, 07:23 AM 7275914911
Still trying to start the motor without success.
... Dec 18 2009, 01:06 PM jhelgesen This morning, I broke down and sucked the smidgen ... Dec 19 2009, 11:06 AM ClayPerrine
This morning, I broke down and sucked the smidgen... Dec 19 2009, 04:45 PM jhelgesen Okay, I'm getting close. One the phone last n... Dec 20 2009, 10:46 AM jhelgesen Ah the web is a wonderful thing....
http://i184.p... Dec 20 2009, 10:56 AM RRietman John; With ign on, you should have 12v to the inje... Dec 20 2009, 11:36 AM jhelgesen :Qarl: :cheer: :headbanger:
Picked up a handfu... Dec 20 2009, 04:13 PM wrightee
Here is the offending resistor.
and my temporar... Dec 20 2009, 05:03 PM stepuptotheMike Sweetness John! Good to hear you got it runni... Dec 20 2009, 04:54 PM jhelgesen The resistor is in the fuel pump relay, circuit fr... Dec 20 2009, 05:14 PM type47 Wow... fixing a resistor in a relay, :worship: Dec 20 2009, 06:27 PM ClayPerrine You need to buy a replacement double relay, if onl... Dec 20 2009, 09:10 PM davesprinkle Good job tracking down and fixing that problem. E... Dec 20 2009, 10:03 PM computers4kids and, believe it or not, the seal under the oil fil... Dec 20 2009, 10:55 PM ClayPerrine
So your problem was the same as mine, a bad relay... Dec 21 2009, 07:47 AM computers4kids
So your problem was the same as mine, a bad rela... Dec 21 2009, 09:19 AM jhelgesen I have a new relay on order, along with a handfull... Dec 21 2009, 03:20 AM jhelgesen This afternoon, we opened the garage door, started... Dec 24 2009, 07:20 PM |
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