I need some help. Car won't rev or drive properly, I can't get any more RPMs / Power Options

[Steve Thacker]

I have a issue with the driveablility of my car.

First the info

1.\ 1974 2.0L engine. W/ good compression

2.\ Valves have been adjusted and double checked.

3.\ Timing set at 29dgs BTDC running Crane Optical unit, new coil, new wires, new plugs, new trigger points.

4.\ Fuel pressure at 29 lbs and remains steady (AFAIK)

5.\ TPS is new and the setting is dead on per spec.

6.\ Tested fuel injectors and they put out the desired pattern and amount. Checked connects also. They appear good.

7.\ MPS tested and all is good there.

8.\ All new vacuum hoses and they are routed to the proper locations

9.\ New head temp sensor and it measures correct via pblanders FI web page

10.\ Idle is set at 975 and it just hums perfectly.

11.\ Distributor appears to be ok and the pot moves the advance plates when vacuum is applied. Not sure about the centrifugal parts down below.

12.\ Clutch, pressure plate and all is is in good shape. Cable is adjusted perfectly

13.\ Checked grounds. (cleaned ground terminals for F.I harness.)


Here is the issue I'm having. The car takes off good in first, but you can't make it redline if you wanted to. This goes the same for any of the other gears. There is no rev limiter on the system. I can get it to rev past 6000 if I'm setting still. Just not in any gear as I upshift.

It just starts breaking up, when I punch it to the floor. I can even punch it to the floor while in second and and it just fights to get up to speed. The engine roars to life, but it labors doing so. I have to feather the gas to get it to keep the revs steady. You have to shift it fast to get the car up to speed from a light. As it breaks up in between shifts and I have to really hammer the gas. I went back to the bird site and got the instructions to check /set the TPS and that is good to go. I just do not know what the issue is.

I also notice that I can not leave it in fourth on the freeway as the engine just fights to stay at speed. I have to shift into fifth to get the car up to 70 miles per hour. And even then it will break up if I try to punch the gas any further to the floor. It is almost like I have to feather the gas pedal to get it to stay at 70 as any slight movement down on the pedal causes the car to struggle. I cannot get the car over 72 as it labors to go any farther. Something else I notice is the tach will jump up and down once in a while while keeping the gas at a steady place. I checked all behind the dash and other places looking for an electrical issue, but I do not see anything. I even ran a new wire for the ground side of the coil back to the front. No change even after doing this.

My question is. What the hell could cause it to do this?

I have run out of brain cells trying to decipher the issue.

Can anyone help?


THANKS !!!!

[Rand]

Tach jumping makes me think ignition wiring. Make sure the wires and connectors are good, especially around the coil.

[orange914]

i'd suspect fuel delivery, it has the earmarkings of vapor lock or volume delivery problems.

mike

[type47]

only a guess but something to check: not getting enough fuel like a clogged fuel line? rust in tank-> line? any way to verify fuel pump flow rate?

[Rand]

Keep in mind, fuel delivery does not make the tach jump. (IMG:style_emoticons/default/wink.gif)

[orange914]

Keep in mind, fuel delivery does not make the tach jump. (IMG:style_emoticons/default/wink.gif)

but a secondary issue of the engine dieing out/coming to life can bounce the gauge. i would think a detailed discription of the tach. (mis) operation could help out.

[Rand]

Nah.... If electrical is strong as you're driving, the tach doesn't bounce. Even if fuel delivery suffers, tach is still accurate. Not like the car could actually lurch from normal to no RPMs for real.

Don't mean to be argumentative, but just sayin'

If tach is actually following engine RPM and it's dropping because the car is slowing down, then that's one thing. But if tach is bouncing about, that's another.

[markb]

Hmmm, tach jumping. Coil connections?

[Rand]

LOL. Hmm. There's a thought. (IMG:style_emoticons/default/beerchug.gif)

[r_towle]

I think you may need to OHM out the FI harness.
Specifically between the Injectors and ground.
Check the main star ground connection on the top of the case under the plenum.

Also, OHM out the TPS and CHT and Dizzy FI points wiring and the Injectors all to the Plug on the ECU...

Rich

[KELTY360]

I know you said the coil is new, but it could be the problem if it's defective. Might try swapping it out with a known good one to confirm it's operation.

[Dave_Darling]

Try going back to points to remove the Crane from the circuit. Tach bouncing makes me suspect it.

--DD

[r_towle]

Quick test...unplug the wire for the tach. Its not inline.
Its one of the two on the coil from the main harness.
I had a tach short out and it took me a while to figure it out..
Unplug it and see if the tach is the issue...maybe/maybe not...but its a simple enough test.

Rich

[Steve Thacker]

The tach jumping goes somethin like dis. Say for example that I'm cruising up the road at 2500 the tach will sometimes dip to 1900 and then bounce back to the 2500 mark.
It does this sporadically.

On the issue of fuel ( good point guys btw ). When I was building the car. I put in new aluminum fuel line from Jegs. I then tested the line and visually inspected it to make sure I had no kinks or obstructions or other issues. Tank was emptied of the old Jurassic gas and then chemically cleaned internally.


Following Rich's idea I'm going to go out an pull the tach wire from the coil and see if this thing acts the same way. As I would probably lay an egg out of pure joy if it was the issue
( if golden then I'll donate it to the club ), if not...scrambled anyone? (IMG:style_emoticons/default/wink.gif)

If all this does not prove fruitless, then I guess ripping out the Crane unit and go back to points to check that for DD's suggestion.

[Steve Thacker]

I disconnected the neg connection on the coil from the tach. It did not help. So, that eliminates the tach. (IMG:style_emoticons/default/stromberg.gif)

I also pulled out the ignition switch and re-checked the connections. This switch is new also and I have new spares, just in case. Nothing found in the inspection.

[orange914]

i know it's been poo poo'd but i still say you should check for possible vapor lock (overheat soaked rear mounted pump.) or volume delivery (weak pump/fuel filter). it CAN cause the tach to jump with in a reasonable amount(got the t-shirt) as the engine stutters. besides you'll never know unless you check.

a good idea to install an inline fuel pressure gauge (i got a nice 0-60 lbs fluid guage for less than $30 shipped from e-bay). check pressure (29#'s) and volume

does anyone know what volume the 914 should put out? how old is the fuel filter? is your pump rear mounted? does it have all the underside cooling flaps and/or does it run hot?


(IMG:style_emoticons/default/beerchug.gif)

[Steve Thacker]

Well the good thing "and something else I forgot to mention". The pump is up front.
So, no vapor lock. I have a inline gauge in the engine bay and it stays at a constant 29. I think the book calls for 28lbs ?

I have tinkered with the timing from retarding just a hair to advancing ( just a hair ). And that has not hampered the breaking up while getting on the throttle. I'm so fucking aggravated I can't see straight!!!!! I'm going to kill this car!!!!!

[Steve Thacker]

I have pulled the dizzy and I'm going to make sure everything moves real easy.

I also did a search on here and I'm starting to think my 30+ year old fuel injectors may be having issues. I'm going to soak them in a solution in the mrs old hydro-sonic jewelery cleaner. Then I'm going to hook up a couple of D batteries with a on off button and try to force some cleaner back through the inlet with some air from the compressor. Hopefully I'll find some junk or other issues to get this issue resolved.

If that doesn't do the trick. I'm buying all new GL- Sorenson injectors for $59 each and be done with it. I just have this feeling that maybe this is the issue as the symptoms are indicative of fuel starving or a rubber F.I line is crimping / collapsing under full load / WOT. I found a issue on here where someone was having the exact same issue as I'm having.

[Tom]

Have you checked the plugs yet? If the car won't rev freely, it is a good sign that it is not getting air or fuel. After a hard pull on the road, push in the clutch and turn off the ignition. Pick a good low traffic area to do this. Pull the plugs, if they are clean, then that would point toward a fuel delivery problem. If they're dark, may be a plugged air way problem. New filter in air cleaner? Could anything have gotten into the intake runners? You have checked the timing, but may be agood idea to do so again. Are you sure you had the light on the right wire? Not trying to be negative, but these things happen and can drive you crazy. When I wired mine back up the first time, I had the plug wires in the wrong direction on the distributer cap.
Good luck
Tom

[Steve Thacker]

Have you checked the plugs yet? If the car won't rev freely, it is a good sign that it is not getting air or fuel. After a hard pull on the road, push in the clutch and turn off the ignition. Pick a good low traffic area to do this. Pull the plugs, if they are clean, then that would point toward a fuel delivery problem. If they're dark, may be a plugged air way problem. New filter in air cleaner? Could anything have gotten into the intake runners? You have checked the timing, but may be agood idea to do so again. Are you sure you had the light on the right wire? Not trying to be negative, but these things happen and can drive you crazy. When I wired mine back up the first time, I had the plug wires in the wrong direction on the distributer cap.
Good luck
Tom

Tom,
The plugs look ok, but I have to say that the car runs a little rich. I put in a 270 ohm resister inline to the head sensor. I pulled the whole airbox off with filter in tow and closed off any lines to the air box and filter ( less the PCV line ). I then performed another test and the outcome was the same. Bog, bog, bog on tromping the gas.. I have checked the timing until I think I'm ready to cry. I have the firing order set at 1-4-3-2 clockwise. So, I'm good there. As far as anything living or previously living in the intake runners. I can't say. they were clear when I put them in. I love fuel injection, but I wish I could tear this thing down, rebuild it for carbs and forget this whole mess.

Nothing worst than a frustrating problem like this to add more gray hair to the roof.