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benalishhero |
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#1
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
Hey guys, I thought I'd pick your brains on this one. If you could knock some ideas around that would be great. I'm stuck on this one.
First off, all the baseline stuff is in order. e.g. valves, ignition, fuel pressure, vacuum etc.. The motor starts fine cold or warm, and idles fine. However it will not take gas off a stop. It will go with about 1/4 throttle if I feather it. If I punch it immediately it dies. I can also, if up to a fair speed, full throttle it(through the bog) and back it off just a bit and it will take off. Basically it's fine at idle and at full enrich. I'm suspecting a dead-spot in the TPS. (IMG:style_emoticons/default/confused24.gif). Can a bad CHT cause poor acceleration? Enjoy the day Thomas |
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DRPHIL914 |
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#2
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Dr. Phil ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,769 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States ![]() ![]() |
Hey guys, I thought I'd pick your brains on this one. If you could knock some ideas around that would be great. I'm stuck on this one. First off, all the baseline stuff is in order. e.g. valves, ignition, fuel pressure, vacuum etc.. The motor starts fine cold or warm, and idles fine. However it will not take gas off a stop. It will go with about 1/4 throttle if I feather it. If I punch it immediately it dies. I can also, if up to a fair speed, full throttle it(through the bog) and back it off just a bit and it will take off. Basically it's fine at idle and at full enrich. I suspecting a dead-spot in the TPS. (IMG:style_emoticons/default/confused24.gif). Can a bad CHT cause poor acceleration? Enjoy the day Thomas you could disconnect the TPS and see if that makes a difference, if not, check the MPS to see if it is failing. first two things i would do, easy to do, go from there. |
SUNAB914 |
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#3
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Senior Member ![]() ![]() ![]() Group: Members Posts: 698 Joined: 29-December 08 From: Fredericksburg VA Member No.: 9,880 Region Association: South East States ![]() |
Philip is back? Thought he was gone after getting his Boxster!
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benalishhero |
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#4
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
I did disconnect the TPS. No difference.
Vacuum tested MPS= fine Tested primary and secondary coils= fine It's got to be something simple I'm overlooking..... |
DRPHIL914 |
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#5
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Dr. Phil ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,769 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States ![]() ![]() |
Philip is back? Thought he was gone after getting his Boxster! (IMG:style_emoticons/default/bootyshake.gif) (IMG:style_emoticons/default/lol-2.gif) acutually i have a spit personality- kind of - they are both mid-engine (IMG:style_emoticons/default/poke.gif) i have not given up on my d-jet, - it is running Sweeeeeet!!!!! (IMG:style_emoticons/default/happy11.gif) it gets the jackpoint treatment beginning next week , rebuilding the tranny next month so i am still here !!!!! (IMG:style_emoticons/default/aktion035.gif) |
DRPHIL914 |
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#6
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Dr. Phil ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,769 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States ![]() ![]() |
I did disconnect the TPS. No difference. Vacuum tested MPS= fine Tested primary and secondary coils= fine It's got to be something simple I'm overlooking..... i am thinking a blocked fuel line, maybe replace the filter. i have sounds like it is fuel starved. but i could be wrong. (IMG:style_emoticons/default/biggrin.gif) |
billh1963 |
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#7
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Car Hoarder! ![]() ![]() ![]() ![]() Group: Members Posts: 3,402 Joined: 28-March 11 From: South Carolina Member No.: 12,871 Region Association: South East States ![]() |
Philip has been shown the dark side....he likes water cooled cars. Now I'm not the only heretic in SC with a 914 and a water cooled abomination!
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Mikey914 |
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#8
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The rubber man ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 12,680 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None ![]() ![]() |
Sorry mis read- I was thinking it was a TPS issue myself
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benalishhero |
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#9
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
New fuel filter
I did the re track trick. no avail Thanks for the ideas. |
TheCabinetmaker |
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#10
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I drive my car everyday ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 ![]() |
A little more background please. Is this a new problem? Did you do anything to it before this happened? Whats the spark at the points (open them manually with key on) and plugs looks like. Is there any sputtering when it dies, or sucking noises?
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benalishhero |
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#11
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
A little more background please. Is this a new problem? Did you do anything to it before this happened? Whats the spark at the points (open them manually with key on) and plugs looks like. Is there any sputtering when it dies, or sucking noises? Yes, it's a new problem. P+C are new. Gap/dwell are fine. Plugs are a nice tan color. No sputtering or sucking when it dies. Another thing, when i started it for the first time this year(few days ago) it fired right up, idled smoothly for 1min, then idled up to 2k and died. It did this a few times. I figured it was just waking up from its winter sleep. It acted like it was running out of gas. Hasn't done that since, but now the new prob. I somehow think they are related. |
underthetire |
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#12
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,062 Joined: 7-October 08 From: Brentwood Member No.: 9,623 Region Association: Northern California ![]() |
Stuck advance in the Dizzy?
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benalishhero |
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#13
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
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914_teener |
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#14
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,208 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California ![]() |
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benalishhero |
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#15
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
Try swapping out to a known working ECU to elimate it. I was thinking that. Now where to find one in Maine (IMG:style_emoticons/default/idea.gif) ? |
tod914 |
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#16
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,755 Joined: 19-January 03 From: Lincoln Park, NJ Member No.: 170 ![]() |
Is the contact plate on your TPS worn? What's your timing and dwell set to?
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falconfp2001 |
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#17
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Pancho Pantera ![]() ![]() Group: Members Posts: 451 Joined: 5-December 10 From: Downey, CA Member No.: 12,456 Region Association: Southwest Region ![]() |
Have you looked at the trouble shooting section here?
http://members.rennlist.com/pbanders/DJetParts.htm |
Prospectfarms |
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#18
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Member ![]() ![]() Group: Members Posts: 495 Joined: 7-March 11 From: Louisville, KY Member No.: 12,801 Region Association: Upper MidWest ![]() |
Sorry to jump in late, but I'm curious. Did the timing advance under throttle when you set is? Doing that with a light would be an easy way to double check advance plate operation.
I'd think you could tell if it's running too rich and say the plugs looked good so maybe not CHT. No midrange can also be symptom of lean AFM. I assume this is true of d-jet. If distributor checks out, I'd get the car to idle, then start pulling FI things off-line. like the AAR, decal valve, TPS, cold start valve, temp 2, etc. Plug the vac lines as you go. Notice the RPM's and check the throttle response along the way. I've run my 1.7 with only MPS and CHT. If nothing else, you'll eliminate those circuits from suspicion. I did this a lot last year when reviving an unknown motor and it helps. |
benalishhero |
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#19
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Member ![]() ![]() Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States ![]() |
Sorry to jump in late, but I'm curious. Did the timing advance under throttle when you set is? Doing that with a light would be an easy way to double check advance plate operation. I'd think you could tell if it's running too rich and say the plugs looked good so maybe not CHT. No midrange can also be symptom of lean AFM. I assume this is true of d-jet. If distributor checks out, I'd get the car to idle, then start pulling FI things off-line. like the AAR, decal valve, TPS, cold start valve, temp 2, etc. Plug the vac lines as you go. Notice the RPM's and check the throttle response along the way. I've run my 1.7 with only MPS and CHT. If nothing else, you'll eliminate those circuits from suspicion. I did this a lot last year when reviving an unknown motor and it helps. Yes the timing did/does advance with the throttle. I did set it with a light. 27 degrees btdc with bellows disconnected. I forgot to mention that the symptoms are present hot or cold..... I guess I'm onto testing the wiring harness... |
Prospectfarms |
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#20
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Member ![]() ![]() Group: Members Posts: 495 Joined: 7-March 11 From: Louisville, KY Member No.: 12,801 Region Association: Upper MidWest ![]() |
Double check the fuel pressure first. Clamp a pressure gauge, any 1-30+ psi gauge you can get your hands on to the test nipple on fuel rail.
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