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> D-Jet Conversion not going as planned., Car starts but will not run.
slapshot
post Oct 18 2024, 03:08 PM
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I am converting back to D-Jet and my car will start but dies right after. It will not rev up applying throttle. I have a 1975 914 2.0. It was running great with Weber 40s prior.

The D-Jet system is from a 1974 2.0. All the parts came in visibly good condition. TPS calibrates good, AAV tested good, Thermo sensor good, air intake temp sensor good, and a new cylinder head temp sensor. The only test that I think is failing is the vacuum test on the MPS. It leaks. Video of testing the MPS.. The MPS has also been rebuilt at some point. The original part # has been removed. There's a good chance it is not calibrated for my car. I have all new vacuum hose and fuel pressure is between 28 and 30.

I don't have any tools to calibrate the MPS. Should I try turning the inner screw on the MPS to see if it helps? Or should I send it to someone to have it rebuild again and recalibrated? If the later do you have any recommendations on who to send it to?
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slapshot
post Oct 21 2024, 11:08 PM
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I inserted a noid light on each injector wires, except the cold start injector, and they all lit up during crank. Does this indicate that the 123 distributor trigger wires are communicating to the ECU and the ECU is working properly?

QUOTE(rjames @ Oct 21 2024, 06:27 PM) *

Just noticed that you stated early in the thread that it looks like someone used the Tangerine kit to rebuild your MPS. If that's the case, the diaphragm is likely fine since the kits haven't been around for that long. More likely that the rebuilder wasn't able to get the MPS case to seal properly as it can be tricky to do.

I did open the body of the MPS and yes the diaphragm on the top is brass and looks like the one on the tangerine racing website. Maybe they all are brass, I don't know. Its definitely been rebuilt. When I put my ear up to it with vacuum, it sounded like it was leaking through the top vents. I taped them off and check and it is. With the tape, the vacuum just barely leaks at all.

QUOTE(dr914@autoatlanta.com @ Oct 21 2024, 08:59 AM) *

no calibration necessary, make sure that you have good dwell and timing and fuel pressure as you crank the car, and that the trigger points are plugged in to start, we can work through this but many variables to deal with since it is a fresh installation. (you can also spray some brake clean into the throttle body to make sure that it keeps running to totally eliminate the ignition system

I have a 123 distributor so no dwell to mess with. Trigger points are plugged in. Starter fluid in the TB seems to just flood it. I agree, lots of variables. I'm 99% sure my timing is spot on since it was before I started this conversion but I'm getting to the point that I can't assume anything is correct. I have a fuel pressure gauge in line between the two fuel rails and the pressure is at 28.

QUOTE(rjames @ Oct 21 2024, 03:23 PM) *

You won't damage the engine. Adjusting the inner screw clockwise will lean out the mixture, counter-clockwise will richen the mixture. It's farily sensitive, which is why I only suggested 1/4-1/2 a turn, but you won't break anything if you go further. Note that you need the Tangerine Racing adjusting tool so that you don't also turn the outer screw that the inner screw sits in (not the outer screw you're talking about which is more commonly referred to as the full-load stop screw).

I'm not sure I follow on what is the full-load stop screw. Is that just the outer allen wrench nut? Here's a pic of the top of mine.


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Spoke
post Oct 22 2024, 02:37 AM
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QUOTE(slapshot @ Oct 22 2024, 01:08 AM) *
Starter fluid in the TB seems to just flood it.


Does it run at all? Are you giving it 100% starter fluid as it is cranked or just short bursts while cranking? It would seem that some bit of starter fluid would make it run but too much might flood it.
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Posts in this topic
slapshot   D-Jet Conversion not going as planned.   Oct 18 2024, 03:08 PM
fiacra   Not the person to ask about how to calibrate your ...   Oct 18 2024, 03:54 PM
slapshot   Not the person to ask about how to calibrate your...   Oct 18 2024, 04:41 PM
Robarabian   Easy Supplier with warranty as well: https://fuel...   Oct 18 2024, 05:30 PM
JeffBowlsby   Try manually pumping the MPS up to 15 inHg and sta...   Oct 18 2024, 04:28 PM
slapshot   Try manually pumping the MPS up to 15 inHg and st...   Oct 18 2024, 04:44 PM
JeffBowlsby   dbl post   Oct 18 2024, 04:30 PM
Craigers17   I’m sure you’ve already checked this off on yo...   Oct 18 2024, 04:53 PM
slapshot   I’m sure you’ve already checked this off on y...   Oct 18 2024, 05:03 PM
JeffBowlsby   Post a photo of how the 123 wires are installed to...   Oct 18 2024, 04:57 PM
slapshot   Here's a pic and a pic of the diagram from wha...   Oct 18 2024, 05:12 PM
JeffBowlsby   Thx, that’s trigger points connection and looks ...   Oct 18 2024, 06:19 PM
TheCabinetmaker   Do you hear the fuel pump come on for a half secon...   Oct 18 2024, 05:42 PM
slapshot   Do you hear the fuel pump come on for a half seco...   Oct 18 2024, 07:27 PM
JeffBowlsby   Are you getting spark at the plugs? Injectors ver...   Oct 18 2024, 07:38 PM
slapshot   Are you getting spark at the plugs? Injectors ve...   Oct 18 2024, 10:37 PM
emerygt350   Can you keep it running with starter fluid?   Oct 18 2024, 07:38 PM
slapshot   Can you keep it running with starter fluid? I tr...   Oct 18 2024, 10:48 PM
JamesM   I am converting back to D-Jet and my car will sta...   Oct 18 2024, 08:49 PM
emerygt350   That is very strange. Have you checked the oil? ...   Oct 19 2024, 07:47 AM
slapshot   The CHT resistance is 2150 @ 65 degrees.   Oct 19 2024, 10:29 AM
emerygt350   That seems reasonable.   Oct 19 2024, 03:29 PM
emerygt350   One thing you could try is lowering the fuel press...   Oct 19 2024, 03:32 PM
slapshot   I will try that.   Oct 19 2024, 04:14 PM
slapshot   No change after turning it down to 24. The engine ...   Oct 20 2024, 12:27 PM
Spoke   The engine starts while cranking but dies a second...   Oct 21 2024, 12:27 PM
slapshot   The engine starts while cranking but dies a secon...   Oct 21 2024, 01:57 PM
Spoke   [quote name='Spoke' post='3173882' date='Oct 21 2...   Oct 21 2024, 02:11 PM
brant   fuel spark timing I would verify spark with a tim...   Oct 20 2024, 12:33 PM
slapshot   I'm not able to check timing since it will not...   Oct 20 2024, 01:24 PM
emerygt350   "and it wouldn’t crank over for a while...   Oct 20 2024, 05:06 PM
slapshot   After spraying a good amount of starter fluid into...   Oct 20 2024, 07:48 PM
JeffBowlsby   Do you know if this ECU is functioning? You can h...   Oct 20 2024, 08:00 PM
slapshot   I don't know. I'll get a noid light tomorr...   Oct 20 2024, 09:48 PM
emerygt350   Again, i am confused by " it would not crank ...   Oct 21 2024, 07:00 AM
slapshot   Again, i am confused by " it would not crank...   Oct 21 2024, 11:39 AM
dr914@autoatlanta.com   no calibration necessary, make sure that you have ...   Oct 21 2024, 08:59 AM
rjames   As MJames stated, the MPS is critical. Yes you...   Oct 21 2024, 11:29 AM
slapshot   As MJames stated, the MPS is critical. Yes yo...   Oct 21 2024, 01:50 PM
rjames   As MJames stated, the MPS is critical. Yes y...   Oct 21 2024, 03:23 PM
JamesM   How sensitive is that inner screw? If I move it ...   Oct 23 2024, 04:07 PM
emerygt350   And I don't think the injector timing will mat...   Oct 21 2024, 06:15 PM
rjames   Just noticed that you stated early in the thread t...   Oct 21 2024, 06:27 PM
sixnotfour   no injection..   Oct 21 2024, 06:51 PM
slapshot   I inserted a noid light on each injector wires, ex...   Oct 21 2024, 11:08 PM
Spoke   Starter fluid in the TB seems to just flood it. ...   Oct 22 2024, 02:37 AM
slapshot   I sprayed starter fluid into an open TB for two or...   Oct 22 2024, 06:05 AM
slapshot   Here's a link to video of noid light test from...   Oct 22 2024, 06:26 AM
rjames   Yes, the outer most screw is the full load stop ...   Oct 22 2024, 09:00 AM
Superhawk996   Tangerine directions   Oct 22 2024, 09:42 AM
slapshot   I haven't pulled out the diaphragm on mine. I...   Oct 22 2024, 10:41 AM
emerygt350   To adjust it, as others mentioned, you need the sp...   Oct 22 2024, 10:42 AM
slapshot   Here's a video of attemping startup..   Oct 22 2024, 03:19 PM
Artfrombama   Here's a video of attemping startup.. I...   Oct 22 2024, 04:49 PM
brant   [quote name='slapshot' post='3174041' date='Oct 2...   Oct 22 2024, 05:07 PM
slapshot   [quote name='slapshot' post='3174041' date='Oct ...   Oct 22 2024, 05:20 PM
emerygt350   Sounds like really retarded timing. Sounds good o...   Oct 22 2024, 05:26 PM
brant   Go back to the basics Pull the distributor Put t...   Oct 22 2024, 06:25 PM
sixnotfour   switch the fuel fuel lines   Oct 22 2024, 06:48 PM
slapshot   You all were right. I pulled the dist, set TDC an...   Oct 22 2024, 07:04 PM
Artfrombama   You all were right. I pulled the dist, set TDC a...   Oct 22 2024, 09:27 PM
slapshot   Thanks to all that contributed. It sure is great ...   Oct 22 2024, 10:34 PM
emerygt350   Now you can get down to the fun of d-jet. Set you...   Oct 23 2024, 05:17 AM
FlacaProductions   I've read that "canned air" (Dust-Of...   Oct 23 2024, 02:30 PM
brant   Agreed Don’t touch the MPs any more until you h...   Oct 23 2024, 04:52 PM
rjames   You can make a cheap homemade smoke 'machine...   Oct 23 2024, 04:53 PM
JeffBowlsby   Even if someone were to calibrate an MPS for you,...   Oct 23 2024, 05:24 PM
slapshot   Also, do you know if they changed the cam on your...   Oct 24 2024, 06:58 AM
brant   Did you set the timing with a strobe light yet? A...   Oct 23 2024, 05:04 PM
slapshot   I have a smoke box and pushed smoke through it tod...   Oct 23 2024, 10:34 PM
emerygt350   You can do that without moving the screws. It rea...   Oct 24 2024, 05:31 AM
slapshot   You can do that without moving the screws. It re...   Oct 24 2024, 07:20 AM
rjames   [quote name='emerygt350' post='3174192' date='Oct...   Oct 24 2024, 10:09 AM
slapshot   After you open the MPS there are 4 screws that ho...   Oct 24 2024, 03:37 PM
emerygt350   [quote name='rjames' post='3174214' date='Oct 24 ...   Oct 24 2024, 05:47 PM
brant   I would get the tuned first You can’t expect it...   Oct 24 2024, 08:40 AM
slapshot   With the smoke test, I get smoke coming out each s...   Oct 25 2024, 08:42 AM
rjames   With the smoke test, I get smoke coming out each ...   Oct 25 2024, 12:37 PM
slapshot   With the smoke test, I get smoke coming out each...   Oct 25 2024, 01:02 PM
brant   It’s rebuildable But no kit A difficult job with...   Oct 25 2024, 09:07 AM
emerygt350   It’s rebuildable But no kit A difficult job wit...   Oct 25 2024, 10:49 AM
slapshot   Now the BIG issue. I am working on setting the ti...   Oct 25 2024, 11:52 AM
slapshot   I set the timing even though I'm confused on w...   Oct 25 2024, 01:18 PM
emerygt350   That throttle shaft leak will add some rpms, is yo...   Oct 25 2024, 03:28 PM
slapshot   I have the retard hose plugged into the dizzy but ...   Oct 25 2024, 05:40 PM
r_towle   What is your dwell? Timing set with no vacuum?   Oct 25 2024, 06:31 PM
r_towle   Also, have you cleaned and re greased the advance ...   Oct 25 2024, 06:34 PM
emerygt350   It is a 123 towle, at least I think it is. I wo...   Oct 25 2024, 06:56 PM
emerygt350   I suspect your misfires and stalls are timing and ...   Oct 25 2024, 06:58 PM
slapshot   I do have a 123 dizzy so no dwell to mess with and...   Oct 25 2024, 09:12 PM
emerygt350   I use a boroscope to ensure tdc, but what you did ...   Oct 26 2024, 05:46 AM
slapshot   I use a boroscope to ensure tdc, but what you did...   Oct 26 2024, 10:26 AM
JamesM   That's a lot of advance at idle. Likely kicki...   Oct 26 2024, 03:09 PM
emerygt350   That's a lot of advance at idle. Likely kick...   Oct 26 2024, 04:50 PM
slapshot   That's a lot of advance at idle. Likely kic...   Oct 28 2024, 10:50 AM
emerygt350   [quote name='emerygt350' post='3174553' date='Oct...   Oct 28 2024, 11:32 AM
Geezer914   There are throttle body shaft seals you can order.   Oct 26 2024, 06:59 AM
slapshot   There are throttle body shaft seals you can order...   Oct 26 2024, 10:06 AM
emerygt350   Well, looks like that TPS board is in your future....   Oct 26 2024, 12:25 PM
emerygt350   If it's looking lean and you want to richen it...   Oct 28 2024, 11:34 AM
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