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Jackba |
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#1
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Hello,
I’ve read through quite a few posts on this subject While working through the problem but I’m still stuck. I hope someone can point me in the right direction. This is an original car with FI. Car was cutting out while on the freeway. Was able to get it home. Weeks later I got back to it, started it and took it on a test drive. It was cutting out even worse on local streets. Got it home. Posted on the site and the advice was to pull and clean distributor. Did that and checked trigger points ignition points and cap. Looked good. Changed condenser. Checked all wires and saw nothing out of place. Removed and checked and cleaned the board on throttle body. Very clean with minimal tracing. Hooked up battery and turned key to on 4 times. Fuel pump running. Pressed accelerator to check for 20 clicks. Then tried to start. Cranks well and catches then dies after one revolution. Tried again several times and it only cranks. Tried again and it catches and runs well for 3 seconds. This was repeated many times in no particular order. Still won’t run. I rechecked the static timing again and went through the same process and got the same results. Next I plan to pull the fuel filter and injectors and see if I’m getting fuel. If no fuel in the rails could it be the fuel pump even though it runs for 1.5 seconds each time I turn on the ignition? Fuel pump is 3 port and probably original to the car. Any other ideas are welcome. Thanks in advance, Jack |
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JeffBowlsby |
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#2
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914 Wiring Harnesses & Beekeeper ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,907 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None ![]() ![]() |
Lubed the dizzy weights recently? The FWSM recommends 1 drop of 30 wt oil in the center of the dizzy shaft, annually. Not lubing them causes the weights to stick and erratic acceleration problems.
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Chi-town |
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#3
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Senior Member ![]() ![]() ![]() Group: Members Posts: 851 Joined: 31-August 18 From: Disneyland Member No.: 22,446 Region Association: Southern California ![]() |
Get an actual gauge on the fuel pressure
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jagalyn |
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#4
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True Patina ![]() ![]() Group: Members Posts: 414 Joined: 31-January 06 From: Scandia, MN Member No.: 5,503 Region Association: None ![]() ![]() ![]() |
This happened to me... same symptoms. Replaced the fuel pump and it fixed the problem. My 73 3port pump was original also.
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dr914@autoatlanta.com |
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#5
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,161 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None ![]() |
connect a fuel pressure gauge between the two left drivers injectors and make sure that you have fuel pressure 28 lbs as you crank.
If so remove the one injector lead and connect a bosch noid light and see if it blinks when cranking. Also you can spray some brake clean into the intake boot and see if it will run steadily Hello, I’ve read through quite a few posts on this subject While working through the problem but I’m still stuck. I hope someone can point me in the right direction. This is an original car with FI. Car was cutting out while on the freeway. Was able to get it home. Weeks later I got back to it, started it and took it on a test drive. It was cutting out even worse on local streets. Got it home. Posted on the site and the advice was to pull and clean distributor. Did that and checked trigger points ignition points and cap. Looked good. Changed condenser. Checked all wires and saw nothing out of place. Removed and checked and cleaned the board on throttle body. Very clean with minimal tracing. Hooked up battery and turned key to on 4 times. Fuel pump running. Pressed accelerator to check for 20 clicks. Then tried to start. Cranks well and catches then dies after one revolution. Tried again several times and it only cranks. Tried again and it catches and runs well for 3 seconds. This was repeated many times in no particular order. Still won’t run. I rechecked the static timing again and went through the same process and got the same results. Next I plan to pull the fuel filter and injectors and see if I’m getting fuel. If no fuel in the rails could it be the fuel pump even though it runs for 1.5 seconds each time I turn on the ignition? Fuel pump is 3 port and probably original to the car. Any other ideas are welcome. Thanks in advance, Jack |
Jackba |
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#6
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Thanks very much guys. I’ll get on this tomorrow.
Hi Jeff, I oiled the center of distributor when I had it out for cleaning/inspection. Thanks for weighing in and for your help with the FI testing and trigger points plug. All went in nicely. Jack |
iankarr |
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#7
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The wrencher formerly known as Cuddy_K ![]() ![]() ![]() ![]() Group: Members Posts: 2,556 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region ![]() ![]() |
I’ve had similar issues. The intermittent cutting out on the road turned out to be a rusty gas tank / clogged filter. Turning over but not continuing to run was due to kinked fuel lines under the tank. Fuel starvation was the culprit in both cases.
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GregAmy |
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#8
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,490 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States ![]() ![]() |
Same symptoms here, issue was poor connections in the wiring harness to replay plate. Resolution was light spreading and cleaning of the male split pins and dielectric grease.
So you have a nice round set of things to check. |
injunmort |
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#9
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,024 Joined: 12-April 10 From: sugarloaf ny Member No.: 11,604 Region Association: North East States ![]() |
as mentioned, clean the sock in the tank and change filter, start there.
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Jackba |
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#10
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Following up on my original post, here’s what I’ve done per suggestions received:
Checked fuel pressure on driver side rail. 30# while cranking. After cranking pressure dropped to 20#s and held that pressure for 20 minutes or so until I removed the gauge. Rented a Noid light kit and and determined that power was present at the plugs. Changed the fuel filter. Opened it up and it looked clean between the flutes. Pulled two injectors and did a spray test on the bench with carb cleaner and 3 volt battery. Pattern looked good with no hesitation. Injectors are about 2 years old and run for about 2,000 miles. Removed relays from relay plate and cleaned all connections including the two multi pin terminals, fuse holders and the other 3 plugs. When I plugged everything back in the fuel pump didn’t work. Really?? Then went through a troubleshooting routine found on Bowlsby.net and discovered an open fuel pump circuit. All the activity on the plate probably caused a connection to be broken. Ordered a relay plate from Brad Mayeur and that fixed the problem with the fuel pump. Rechecked static timing. After each of these tasks I attempted to start the car. Same result except it did sound more eager to keep running.... Three years ago I had the tank out and pulled the sock which was actually clean and the tank wasn’t rusty. I was trying everything else before resorting to draining and pulling the tank. I pulled the plate under the tank and inspected the lines for kinks and found none. Then I pulled the incoming line from the filter and started draining the tank into a series of gas cans. The fuel flowed without resistance or hesitation, all five gallons and it was clean. I’d really like to avoid pulling the tank if I don’t need to. Have I missed anything? Any other ideas? Running out of patience! Thanks in advance, Jack |
Spoke |
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#11
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Jerry ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,158 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None ![]() ![]() |
Did you check the CHT sensor resistance? I think it should be 2500 ohms cold and 150 ohms hot.
If you think it might be fuel related, spray some starting fluid in the intake and see if it fires up for a few seconds. |
Jackba |
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#12
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Thanks Jerry. I haven’t checked the CHT resistance but I will tomorrow.
I sprayed starter fluid into the TB and I got the same result as if I hadn’t. Tries to start then doesn’t |
Jackba |
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#13
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Using a digital MM the sensor read resistance of ~3000 ohms which is consistent with info found on Brad Anders’ page.
Other thoughts are more than welcome. |
Jackba |
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#14
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Pulled the tank, just to rule it out. Some debris on the lower part of the sock but nothing that would restrict flow. Also pulled the last two injectors and checked the spray pattern. Good.
Unfortunately it still won’t start. So here’s a summary of all steps taken to get it back on the road. Symptoms: Cutting out on the freeway. Got it home. After some time, started the car and drove it around the block. Bucking badly. Changed condenser Disassembled distributor and ultrasonically cleaned all components Fresh grease between the plates New points Inspected trigger points Centered trigger points using ohmmeter and rotating shaft. Reassembled distributor. Set points and static timed to #1 at TDC Attempted to start. Turns over but won’t catch and run Checked fuel pressure: 30 #s Checked injector plugs with Noid light. All good Cleaned relay plate relays and contacts Now fuel pump doesn’t run... Diagnosed open circuit on relay plate Installed replacement relay plate from Brad Mayeur Fuel pump running Changed fuel filter. Not clogged very little residue Tried to start with starter fluid. Starts and runs for 2-3 seconds then dies.,same as with fuel only Pulled injectors and bench cleaned with carb cleaner and 3v battery. No gunk. Good spray pattern. Reinstalled injectors checked injector plug fit. Good and tight Pulled fuel tank. Some residue on bottom of sock but nothing that would restrict flow. Reinstalled tank and added 3 gallons of fresh gas. Verified resistance at the CHT at ~ 3000 ohms @ room temp Still won’t start... So, I have spark, I have fuel and throttle body is clean with a recent TPS board that shows very little wear. Injectors are working. What am I missing? |
Spoke |
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#15
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Jerry ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,158 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None ![]() ![]() |
Changed condenser I'm not a fan of points and condenser. Pertronix and other solid state or CD solutions are much better and reliable. Not saying this is your issue, just saying I'd never run points and condenser again. QUOTE Centered trigger points using ohmmeter and rotating shaft. Reassembled distributor. Not sure what you mean about "centered trigger points. So you verified with an ohmmeter that the contacts open and close? It just seems that your engine is not getting fuel when running. The fuel pump pressurizes the system and you get 2-3 seconds of running then dies. It just seems like the fuel pump isn't running when trying to run the engine. QUOTE Attempted to start. Turns over but won’t catch and run You said before the engine runs 2-3 seconds then dies. Is that still the operation? QUOTE Checked fuel pressure: 30 #s I'm assuming you measured the fuel pressure while cranking the engine. Is the fuel pump running when you did the measurement? QUOTE Tried to start with starter fluid. Starts and runs for 2-3 seconds then dies.,same as with fuel only I wonder if you kept spraying starter fluid if the engine would continue to run. Have you tried a test like this? You'd need someone to crank the engine while you stay in the engine compartment spraying starting fluid. If the engine continues to run then you know it's fuel related. BTW, with all the work you're doing on the engine, have you removed the engine lid to give better access? I do this now when changing plugs and such if it's a long job. I've even grinded the oval mounting hole on the lid hinge so I don't have to remove the securing bolts. Working on the engine with the lid in place really cramps things up. |
bobboinski |
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#16
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Member ![]() ![]() Group: Members Posts: 200 Joined: 23-April 16 From: Petaluma Member No.: 19,929 Region Association: Northern California ![]() ![]() |
Definitely not an expert but I have had situations where fuel pressure was ok but volume was insufficient. Maybe try disconnecting a fuel line at the engine nearest an injector and pump fuel into a container, just to be sure you are getting a good volume of fuel to the engine. My apologies if you have already done this.
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Jackba |
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#17
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Thanks for hanging in with me, Spoke!
First off, I removed the engine lid early on in this process. Big improvement! I agree with you regarding Pertronix and the like. At this time I didn’t want to introduce another variable. 2-3 seconds of running is the best I’ve achieved. Mostly it just repeatedly catches but that’s it. Trigger points: at first I didn’t see any flashes from the Noid light sini pulled the dist and adjusted the trigger points until I read open and closed between pins 21 and 22. Noid lights flashed on all 4 Fuel pressure reading was taken at the center of driver side rail while engine was cranking. I have not sprayed starting fluid into the TB while engine was cranking but I’ll give it a try. Bobboinski, I’m not an expert either so thanks for weighing in with a good suggestion which I haven’t tried. I can tell you that when I pulled each injector an ample amount of fuel collected on the tins below. In the situation you described did you replace the fuel pump? Thanks again, guys. |
dlee6204 |
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#18
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Howdy ![]() ![]() ![]() ![]() Group: Members Posts: 2,162 Joined: 30-April 06 From: Burnsville, NC Member No.: 5,956 ![]() |
A couple things come to mind...
1. Have you checked your MPS to see if it holds vacuum? Based on your description it doesn’t sound like this is the issue however it is super easy to check. 2. The fact that it did run before and now it doesn’t means it could be something you did. Have you verified timing order? You could be 180 degrees off on the distributor. 3. Have you checked to see if you have spark at each lead? Hook the timing light to each lead while cranking. 4. Does it run for 2-3 seconds every time you crank it or does it only do it once before you have to wait and try again later? 5. Finally I’d try rotating the distributor a few mm in either direction to see if advancing or retard the timing gets it to stay running longer. 6. Clean your FI grounds. Don’t just check them but remove and clean making sure they are a snug fit. |
bobboinski |
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#19
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Member ![]() ![]() Group: Members Posts: 200 Joined: 23-April 16 From: Petaluma Member No.: 19,929 Region Association: Northern California ![]() ![]() |
Thanks for hanging in with me, Spoke! First off, I removed the engine lid early on in this process. Big improvement! I agree with you regarding Pertronix and the like. At this time I didn’t want to introduce another variable. 2-3 seconds of running is the best I’ve achieved. Mostly it just repeatedly catches but that’s it. Trigger points: at first I didn’t see any flashes from the Noid light sini pulled the dist and adjusted the trigger points until I read open and closed between pins 21 and 22. Noid lights flashed on all 4 Fuel pressure reading was taken at the center of driver side rail while engine was cranking. I have not sprayed starting fluid into the TB while engine was cranking but I’ll give it a try. Bobboinski, I’m not an expert either so thanks for weighing in with a good suggestion which I haven’t tried. I can tell you that when I pulled each injector an ample amount of fuel collected on the tins below. In the situation you described did you replace the fuel pump? Thanks again, guys. I did end up replacing the fuel pump and that fixed the problem. But if you are getting good volume and pressure I wouldn't think your fuel pump is the problem. |
Jackba |
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#20
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Newbie ![]() Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California ![]() |
Thanks for the additional suggestions, guys.
I verified firing orders, cleaned the FI grounds and... tried more starting fluid than I had used when trying it earlier. It ran long enough that I’m convinced lack of fuel volume is the problem. Plus, several of you cited the fuel pump as the cause your problems that are very similar to mine. I’m confident that the fuel pump is original to the car based on the ownership history and documentation. For $65 I’ll install the Bosch 69133 pump other posters have used. Probably a good thing to do anyway. Once I get it running I’ll install a Pertronics unit. I’ll be away from the car for 7 days. Can’t wait to hear it run again! Thanks for all the help. Jack |
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