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> Starting Problems, Starting with Throttle but Won't Idle
nmkimosabe
post Jul 31 2026, 04:18 PM
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My 1974 1.8 with fuel injection will only start by manually opening the throttle but I can't get it idle and thus run properly. I recently had the AFM rebuilt and replaced the points, plugs, condenser and replaced the CHT sensor but the problem continues as it did before. I've looked for vacuum leaks to no avail with starter fluid. I now seek the expertise of the members of this forum for additional suggestions.
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fiacra
post Aug 1 2026, 01:32 PM
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I'm going to add a few more things I know about this car and the journey that this owner has been. Some of these are from previous threads about this car, and some from personal communication. I suggested he start a new thread to keep things a bit cleaner as circumstances have changed. However I think a recap of things would be helpful so I'll take that on as best I can. Briefly, the car came out of 2 months of winter storage, ran fine for a day, and then while being driven lost power, "chugged," and then died. At that point the car would only start on occasion and then briefly run and then die no matter what. The owner did a bunch of diagnostic work on it, a lot of it suggested by other board members, but no success so it went off to a shop. That shop couldn't solve the problem so it went to a second shop. That shop diagnosed poor compression and leak down numbers (reportedly "less than half of what it should be") but that didn't fit the circumstances and didn't sound right to him so it is now in the hands of a third shop. The current shop found good compression and leak down numbers (!) and basically went right back to the basics with a full tune up (new points, condenser, valve adjustment, etc.) and that has gotten it to the point where it is now - running when given gas but dying at idle. They have diagnosed a bad CHT (even though the current one is new) and have recommended a smoke test for vacuum leaks.

To me, their approach sounds really reasonable. L-Jet won't idle with a vacuum leak (unlike D-Jet) but will keep running with your foot on the gas so a smoke test (vs. using starting fluid) seems appropriate. It is running now with new ignition parts and based on a past similar experience I suspect it had a bad condenser, although I recognize I could easily be wrong.

There has been significant progress in that at least it is running now, but let's help this guy get his car fully sorted out and back on the road. He's had a rough (and expensive) journey to get to this point. I've been as helpful as I can, but you all are a bunch smarter than me and he wants to have meaningful suggestions to give to the shop. So many hands (with dubious skill levels) have been on this car that my money is on a vacuum leak, likely from something getting knocked loose or broken. I think originally the problem lay in the ignition system, and that problem has now been solved with the work done by the current shop. That's my take, but again I know I could easily be wrong.

Here are the previous threads:

http://www.914world.com/bbs2/index.php?sho...=377499&hl=

http://www.914world.com/bbs2/index.php?sho...=377590&hl=
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nmkimosabe   Starting Problems   Jul 31 2026, 04:18 PM
rfinegan   get a smoker from amazon, cheep and multi purpose....   Jul 31 2026, 04:23 PM
nmkimosabe   get a smoker from amazon, cheep and multi purpose...   Aug 1 2026, 11:51 AM
fiacra   I'm going to add a few more things I know abou...   Aug 1 2026, 01:32 PM
fiacra   :popcorn:   Aug 6 2026, 10:29 AM
rfinegan   It is running now with new ignition parts and base...   Aug 6 2026, 11:10 AM
nmkimosabe   It is running now with new ignition parts and bas...   Aug 10 2026, 12:03 PM
TRP   Congratulations on getting it to start and idle. T...   Aug 10 2026, 03:30 PM
nmkimosabe   Congratulations on getting it to start and idle. ...   Aug 10 2026, 09:20 PM
TRP   Congratulations on getting it to start and idle....   Aug 10 2026, 11:36 PM
wonkipop   Congratulations on getting it to start and idle....   Aug 11 2026, 05:07 AM
nmkimosabe   [quote name='nmkimosabe' post='3268296' date='Aug...   Aug 11 2026, 08:54 AM
wonkipop   [quote name='nmkimosabe' post='3268296' date='Au...   Aug 11 2026, 06:01 PM
nmkimosabe   [quote name='nmkimosabe' post='3268355' date='Aug...   Aug 24 2026, 02:23 PM
Artfrombama   I too have a 74 1.8 with FI I was having a similar...   Aug 24 2026, 02:51 PM
wonkipop   Congratulations on getting it to start and idle. ...   Aug 11 2026, 05:25 AM
nmkimosabe   Thanks for the advice and I will double check that...   Aug 26 2026, 09:32 AM
Superhawk996   Find a new mechanic that actually understands thes...   Aug 26 2026, 12:56 PM
wonkipop   Find a new mechanic that actually understands the...   Aug 26 2026, 03:19 PM
wonkipop   as i recall @nmkimosabe - you sent me a PM telli...   Aug 26 2026, 03:47 PM
nmkimosabe   I will try to clarify the status and progress to d...   Aug 27 2026, 06:13 PM
Superhawk996   Given you had a worn distributor is there a reason...   Aug 27 2026, 07:08 PM
nmkimosabe   Given you had a worn distributor is there a reaso...   Aug 28 2026, 04:26 PM
wonkipop   Given you had a worn distributor is there a reas...   Aug 29 2026, 05:06 AM
nmkimosabe   [quote name='nmkimosabe' post='3269962' date='Aug...   Aug 29 2026, 12:02 PM
wonkipop   [quote name='wonkipop' post='3270009...   Aug 29 2026, 02:07 PM
fiacra   I can't believe this saga took yet another tur...   Aug 27 2026, 09:01 PM
nmkimosabe   I can't believe this saga took yet another tu...   Aug 28 2026, 04:27 PM
fiacra   It's funny how things always seem to circle ba...   Aug 29 2026, 07:54 AM
nmkimosabe   It's funny how things always seem to circle b...   Aug 29 2026, 12:06 PM
nmkimosabe   It was suggested to me today by a person with seve...   Sep 5 2026, 05:34 PM
wonkipop   It was suggested to me today by a person with sev...   Sep 6 2026, 07:49 PM
nmkimosabe   [quote name='nmkimosabe' post='3270852' date='Sep...   Sep 7 2026, 03:37 PM
wonkipop   [quote name='nmkimosabe' post='3270852' date='Se...   Sep 7 2026, 05:09 PM
nmkimosabe   [quote name='nmkimosabe' post='3271003' date='Sep...   Sep 8 2026, 12:35 PM
Superhawk996   Not likely. Can be measured if you really wanted...   Sep 5 2026, 08:41 PM
nmkimosabe   Not likely. Can be measured if you really wante...   Sep 6 2026, 05:19 PM
wonkipop   @nmkimosabe situation re servicing /parts etc fo...   Sep 8 2026, 01:00 PM
nmkimosabe   @[url=http://www.914world.com/bbs2/index.php?show...   Sep 9 2026, 11:03 AM
wonkipop   @nmkimosabe re 87 alfa romeo spider. thats a co...   Sep 9 2026, 01:12 PM
nmkimosabe   @[url=http://www.914world.com/bbs2/index.php?show...   Sep 9 2026, 04:16 PM
wonkipop   @nmkimosabe some other tips for you re your 1.8 ...   Sep 9 2026, 01:28 PM
nmkimosabe   [b]@[url=http://www.914world.com/bbs2/index.php?s...   Sep 15 2026, 04:37 PM
Superhawk996   Here is the curve for CHT sensor - you will have a...   Sep 15 2026, 07:28 PM


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