1974 2L fuel injection
Cylinder 2 and 4 not firing below 2800 rpm
Also above 4000 rpm the car bucks terribly
My mechanic says that cylinder 2 and 4 are not firing below 3000 rpm
He check trigger points they are fine
He wants to change to carbs

Any help in solution and should I allow him to move to carbs

No carbs...yet. Budget $800-1000 for the conversion. Member Perry Kiehl Clone is located in TN. You might try contacting him.

Thank you. I will try sending a message hope he lives in Nashville

Strongly suspect your trigger points. Replace them with a new set. I would replace your TPS too, it sounds like it is worn.

ANY wrench that quickly jumps to suggesting carbs on an otherwise good FI system should be avoided as not competent with the FI system. Find another wrench.

Trigger points and tps, agreed.

Additionally I would suggest you clean and degrease the ignition points advance plates and get a new set of points in there.

Trigger points fire injectors in pairs. 1/4 or 2/3 . if 2/4 are not firing together, two of your injectors are wired wrong too. I agree with trigger points, and tps. Two sperate problems. Turn the trigger point plug on the forward of the distributor around. If the non firing cylinders change, you have a trigger point problem, which may just be a loose wire in the plug. They can come loose.

Ah, but are we certain the the mechanic is saying 2/4 correctly?
Hope you understand what I mean.

BTW, find a new mechanic or learn to work on it you self. Lots of knowledgeable members in your state.

of course, rich. I understand. They are numbered on the engine tin remember?

2 and 4 would be the rear two cylinders.

Try a compression test. If those two are lower than the others, you may have a flat cam lobe or two. I hope that isn't it.

--DD

1


1&3 are rear cylinders on my '71 1.7 according to the stampings on the tins

I am in Knoxville but I know a good 914 World guy in Nashville. The great carb FI debate will rage forever. But only make that call when the car is running well. Not to fix a undiagnosed problem.

You are correct, injunmort

Oops, got them backwards. So 2 & 4 are the front cylinders--they still share cam lobes.

--DD

I concur.

I also suspect injector signals are misplaced (crossed up), but that's long-distance diagnosis (IOW, almost a WAG).

Sherwood

It's hard to diagnose a problem via internet, but you might get lucky.

I'm going to suggest trigger points as the problem. How did your mechanic check the problem?

Are you sure the ignition system is good? There are resistors in the plug wire ends that go bad and you can drop cylinders. Before spending a bunch on parts, narrow down the trouble area. Pull your injectors and see if they spray or not. it would suck to pull the F.I. and find out later the trouble was really ignition related.

Update to all - After many miles and time, Auto Atlanta was able to cure my problem - Their is aground wire in the distributor that was not solder at the factory and over time it starting losing contact. Thank all of you for your guidance and insight