Starting issues. |
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Starting issues. |
bmtrnavsky |
Oct 24 2007, 02:44 PM
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#1
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Member Group: Members Posts: 355 Joined: 20-October 07 From: Longview, TX Member No.: 8,245 Region Association: Southwest Region |
I am having a intermittent issue with starting my 73 2.0L. I am running stock fuel injection and besides a mild cam and hydraulic lifters have a stock motor. So here is the issue...
90% of the time I go to start the car the fuel pump primes and it fires off on the first time or two it compresses... Sometimes if I warm up the car and then shut it down and try to re start it still primes and everything sounds good but the engine turns over and will not fire. If I try 3-4 times it will eventually flood and I will start to smell the gas. If I wait about 30 minutes to a hour and try to start it and it fires right up. It almost sounds like vapor-Lock but I don't think it should do that in 60-70 degree weather??? Any ideas??? |
cassidy_bolger |
Oct 24 2007, 03:04 PM
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#2
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Member Group: Members Posts: 106 Joined: 17-March 06 From: = Member No.: 5,737 Region Association: None |
I am having a intermittent issue with starting my 73 2.0L. I am running stock fuel injection and besides a mild cam and hydraulic lifters have a stock motor. So here is the issue... 90% of the time I go to start the car the fuel pump primes and it fires off on the first time or two it compresses... Sometimes if I warm up the car and then shut it down and try to re start it still primes and everything sounds good but the engine turns over and will not fire. If I try 3-4 times it will eventually flood and I will start to smell the gas. If I wait about 30 minutes to a hour and try to start it and it fires right up. It almost sounds like vapor-Lock but I don't think it should do that in 60-70 degree weather??? Any ideas??? I have the same problem! I run a few errands and then it won't start for an hour or more. If it has sat for 4 hours or more, never a problem. Recent tune up, points etc.....Is the fuel pump beginning to fail and vapor lock more easily? For me, this is new after 1.5 years of no starting problems. Stock FI and pump location. |
Jeffs9146 |
Oct 24 2007, 03:17 PM
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#3
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Ski Bum Group: Members Posts: 4,062 Joined: 10-January 03 From: Discovery Bay, Ca Member No.: 128 |
Does it start to run funny after it is warmed up? Maybe the CHT sensor!
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bmtrnavsky |
Oct 24 2007, 03:22 PM
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#4
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Member Group: Members Posts: 355 Joined: 20-October 07 From: Longview, TX Member No.: 8,245 Region Association: Southwest Region |
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TravisNeff |
Oct 24 2007, 03:31 PM
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#5
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914 Guru Group: Members Posts: 5,082 Joined: 20-March 03 From: Mesa, AZ Member No.: 447 Region Association: Southwest Region |
Coil getting too hot?
Brad Anders resaerched the hot start issue, and once the engine is turned off then back on again (after fully warmed up) the FI system will run rich for a bit. |
orthobiz |
Oct 24 2007, 05:37 PM
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#6
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Senior Member Group: Members Posts: 1,754 Joined: 8-January 07 From: Cadillac, Michigan Member No.: 7,438 Region Association: Upper MidWest |
Sounds like classic vapor lock, no?
Seem to happen more on hot days? Easy to try keeping the tank full in the hot weather. Also, avoid ethanol-containing gas wherever possible. Paul |
Rand |
Oct 24 2007, 05:44 PM
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#7
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
NO!!!! No offense Paul, you are just sharing stuff you've heard. Sorry if I sound krusty. No offense intended. But vapor lock is mostly a farce.
THIS is not vapor lock! As etherial as that mythical problem is, I promise it's not the case here and now. I question that always, but this is Winter in the Pacific NW, so even more than ever I say BAH!!!! From what I understand, when this problem occurs, we don't hear the fuel pump running (on a 73 2.0, so fuel pump should hum when key on.... for a sec, then should run when cranking and running). If you determine for sure that the fuel pump isn't running then you can run through some steps to narrow it down.... How are the connectors at the pump? Put a meter on it - is there power at the pump? You could also make some jumper wires (I have some on hand with alligator clips at each end that are handy for stuff like this) and put power directly to the fuel pump terminals to see if it runs. |
Jeffs9146 |
Oct 24 2007, 05:59 PM
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#8
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Ski Bum Group: Members Posts: 4,062 Joined: 10-January 03 From: Discovery Bay, Ca Member No.: 128 |
QUOTE If I try 3-4 times it will eventually flood and I will start to smell the gas. Cant be the fuel pump with flooding. |
bmtrnavsky |
Oct 24 2007, 06:02 PM
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#9
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Member Group: Members Posts: 355 Joined: 20-October 07 From: Longview, TX Member No.: 8,245 Region Association: Southwest Region |
NO!!!! No offense Paul, you are just sharing stuff you've heard. Sorry if I sound krusty. No offense intended. But vapor lock is mostly a farce. THIS is not vapor lock! As etherial as that mythical problem is, I promise it's not the case here and now. I question that always, but this is Winter in the Pacific NW, so even more than ever I say BAH!!!! From what I understand, when this problem occurs, we don't hear the fuel pump running (on a 73 2.0, so fuel pump should hum when key on.... for a sec, then should run when cranking and running). If you determine for sure that the fuel pump isn't running then you can run through some steps to narrow it down.... How are the connectors at the pump? Put a meter on it - is there power at the pump? You could also make some jumper wires (I have some on hand with alligator clips at each end that are handy for stuff like this) and put power directly to the fuel pump terminals to see if it runs. My fuel pump is running normally, and it actually floods the engine if I try to many times to start it... Thats what has me so stumped... and your right, it seems like it is way to cool right now to be vapor-locking this time of year at 9PM. |
Rand |
Oct 24 2007, 06:18 PM
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#10
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
NO!!!! No offense Paul, you are just sharing stuff you've heard. Sorry if I sound krusty. No offense intended. But vapor lock is mostly a farce. THIS is not vapor lock! As etherial as that mythical problem is, I promise it's not the case here and now. I question that always, but this is Winter in the Pacific NW, so even more than ever I say BAH!!!! From what I understand, when this problem occurs, we don't hear the fuel pump running (on a 73 2.0, so fuel pump should hum when key on.... for a sec, then should run when cranking and running). If you determine for sure that the fuel pump isn't running then you can run through some steps to narrow it down.... How are the connectors at the pump? Put a meter on it - is there power at the pump? You could also make some jumper wires (I have some on hand with alligator clips at each end that are handy for stuff like this) and put power directly to the fuel pump terminals to see if it runs. My fuel pump is running normally, and it actually floods the engine if I try to many times to start it... Thats what has me so stumped... and your right, it seems like it is way to cool right now to be vapor-locking this time of year at 9PM. Thanks for the update Brad. Last night I thought I heard talk about the fuel pump not running. (I thought we talked about not hearing the pump run when the key was turned on for a sec?) If the fuel pump is running then we have a whole new troubleshooting track to explore. I know for sure this is not a vapor lock issue. |
cooltimes |
Oct 24 2007, 06:37 PM
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#11
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Advanced Member Group: Members Posts: 2,508 Joined: 18-May 04 Member No.: 2,081 Region Association: None |
IMHO
fuel line pressure needs checked. Too little it won't crank and too much it will flood. Also the return line back to the fuel tank can get gummed up and create the same issue and appearance. MikeCooley |
Cap'n Krusty |
Oct 24 2007, 07:41 PM
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#12
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
Fuel pressure 29-30PSI? Vacuum system intact and well sealed? MPS (and the hose) good? Valve adjustment (I realize it's hydraulic)? Cam profile too radical for MPC EFI? (That's a biggie.) Dwell and timing on the money? Voltage to the coil and the ECU at 11V or better while cranking? (That's another biggie.) Continuity and good solid connections to ALL FI components?
That's it for now. Report back when you've checked ALL that stuff. The Cap'n |
bmtrnavsky |
Oct 25 2007, 11:06 AM
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#13
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Member Group: Members Posts: 355 Joined: 20-October 07 From: Longview, TX Member No.: 8,245 Region Association: Southwest Region |
Fuel pressure 29-30PSI? Vacuum system intact and well sealed? MPS (and the hose) good? Valve adjustment (I realize it's hydraulic)? Cam profile too radical for MPC EFI? (That's a biggie.) Dwell and timing on the money? Voltage to the coil and the ECU at 11V or better while cranking? (That's another biggie.) Continuity and good solid connections to ALL FI components? That's it for now. Report back when you've checked ALL that stuff. The Cap'n valves should be good its only been about 2 months and low miles since last adjustment. Cam is very mild... vacume lines look good. Is there anyone north of Seattle that would want to look at this with me? |
bmtrnavsky |
Oct 25 2007, 07:24 PM
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#14
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Member Group: Members Posts: 355 Joined: 20-October 07 From: Longview, TX Member No.: 8,245 Region Association: Southwest Region |
(IMG:style_emoticons/default/icon_bump.gif)
Anyone North of Seattle that may be able to help me with this issue in real time? |
PeeGreen 914 |
Oct 25 2007, 07:31 PM
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#15
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Just when you think you're done...wait, there is more..lol Group: Members Posts: 10,219 Joined: 21-September 06 From: Seattle, WA... actually Everett Member No.: 6,884 Region Association: Pacific Northwest |
I would love to help Brad, but I am not available until next week. If nobody has come out to help by Monday I will see what I can do.
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bmtrnavsky |
Oct 26 2007, 10:27 AM
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#16
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Member Group: Members Posts: 355 Joined: 20-October 07 From: Longview, TX Member No.: 8,245 Region Association: Southwest Region |
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