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1G 4g37 running problem

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MrDasani

Probationary Member
18
5
Oct 6, 2021
Elk, Washington
ok, ive tried a few things at this point but, the problem is persistent. The car works fine for around 15-30 minutes but after a bit on up rev the rpms start acting spiritic. it quickly goes from 3000 down to 2200 stays there for a sec, 2200 down to 1300, and so on and so forth. then it stalls and wont start after. I've replaces the coolant temp sensor, maf, fixed an oil temp sensor, and it doesnt have an 02 sensor. any ideas on what this could be? the radiator fans dont work either but i dont think that would be related
 
Last edited:
Solution
well, if anyone is interested it has been fixed. the problem was the power transistor, and its part of the distributor. so if you have a problem like this with a 4g37 it might be a distributor. thanks all for the recommendation.
This sounds like it could be a problem with your faiv system, are the coolant lines still connected to the throttle body?
 
well, if anyone is interested it has been fixed. the problem was the power transistor, and its part of the distributor. so if you have a problem like this with a 4g37 it might be a distributor. thanks all for the recommendation.
 
Solution
well, if anyone is interested it has been fixed. the problem was the power transistor, and its part of the distributor. so if you have a problem like this with a 4g37 it might be a distributor. thanks all for the recommendation.
Definitely interested!
A problem that shows up as 'runs okay when cold but has a miss or even stops running completely when fully warm or hot' the first thing I check is ignition -- all parts there (transistor, coil(s), wires, cap, rotor) are more likely to fail under those conditions. The problem may show up first only when pulling power (voltages are highest then) but get worse over time -- an hour to weeks of occasional use.

Dealers can put a scope on the ignition and likely spot the problem.

A trick I've used a couple of times is to replace the plugs with a set gaped 1/3 less. If that makes the problem much better then focusing on the high voltage parts -- substitution or whatever -- is worth the trouble. This works because the smaller gap reduces the high voltage so that the stress on whatever insulation is failing will be less and it won't fail as much ... for a while.
 
Gentlemen, good morning, I'm new here. I live in Brazil and I acquired an Eclipse 91, 4g37, I am the second owner. I'm working on the exact part under discussion, the distributor. I bought the cap, rotor and a coil. However, when reading the information of the discussion, I saw that colleagues said n "transistor". What exactly would this part be, and if it had a problem, would I have to completely replace the distributor? I'm grateful for the answers.

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With my car after I replaced the distributor it started working correctly. Good luck with your car!
Spare parts arrive this week. If it doesn't work, we'll make an adaptation, but we'll use the gear part and the phonic wheel and from there we'll use a system without the cover. If so, I bring the news and how the system was assembled. Already told me the electrical mechanic, which is workable and more reliable.
 
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