1974 1.8L engine fast idle then stalls, Fuel injection issues |
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1974 1.8L engine fast idle then stalls, Fuel injection issues |
tshih914 |
Feb 19 2023, 11:45 PM
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#1
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Member Group: Members Posts: 79 Joined: 17-July 05 From: central NJ Member No.: 4,426 |
My 1.8L 914-4 with stock Bosch L?-Jetronic FI after being stored several years started to develop a hard to start problem. When finally started would stall when I give the gas pedal any input to raise the revs. I suspect there was some kind of intake air leak and while fiddling around had a backfire which blew the AF meter which I had Pelicanparts repaired. After replacing the fuel lines with the stainless ones from Tangerine Racing and flushing out the fuel system with Techron the engine started to run normally for a short time. Now the engine can be started and fast idles at 3000 rpm but again any input to rev up the engine results in stalling. The idle adjustment screw at the base of the throttle housing is fully closed. Any suggestions on how to fix?
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wonkipop |
Feb 26 2023, 01:58 PM
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#2
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Advanced Member Group: Members Posts: 4,667 Joined: 6-May 20 From: north antarctica Member No.: 24,231 Region Association: NineFourteenerVille |
two suggestions by other members re injector seals.
sensible suggestion. i did mine after the sleep along with new injectors. put them on your list to get some if you haven't done them. another thing to get hold of is a throttle body to plenum gasket. 914 rubber has them. worthwhile replacing that regardless. they do go hard with age. pretty cheap little part so its not a heavy investment. and another suggestion the plenum itself can corrode and have pinholes in it is very true. they will likely be underneath and very had to see without getting it off. bit of a job. notice there is a bit of surface corrosion on the intake runners. so its a possibility. smoke test should find them however if they are there. |
tshih914 |
Feb 26 2023, 03:23 PM
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#3
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Member Group: Members Posts: 79 Joined: 17-July 05 From: central NJ Member No.: 4,426 |
two suggestions by other members re injector seals. sensible suggestion. i did mine after the sleep along with new injectors. put them on your list to get some if you haven't done them. another thing to get hold of is a throttle body to plenum gasket. 914 rubber has them. worthwhile replacing that regardless. they do go hard with age. pretty cheap little part so its not a heavy investment. and another suggestion the plenum itself can corrode and have pinholes in it is very true. they will likely be underneath and very had to see without getting it off. bit of a job. notice there is a bit of surface corrosion on the intake runners. so its a possibility. smoke test should find them however if they are there. Considering all recent suggestions my plan going forward is 1) replace all hoses with new (Someone posted that Belmetric sells all hoses but when I looked at their website the search under vacuum hoses gave no results) I also need to know if someone sells a complete kit that allows complete replacement of all vacuum hoses for the 1.8L L-jet (at least list the correct id and length of each hose needed.) 2) replace FI boot (already ordered from AutoAtlanta) 3)replace throttle body to plenum gasket from 914 rubber 4)fuel injectors appear to be fine as the engine was running fine and idled at 3000 rpm so may replace the injector seals which are old. 5) measure the Fuel pressure and adjust the running pressure on FP regulator 35psi and 28 psi 6) systematically go and check/test each component as per factory manual |
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