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> seriously, this is getting annoying..., more fuel injection woes.
mike souza
post Oct 9 2007, 02:17 AM
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ok, so I think I tracked down the reason I've been burning up head temp sensors.
checked the ground strap & it was in bad shape, so I bought a stock replacement & added another ground further up (behind the bell housing to bare metal where motor mount bar bolts)
it ran great!
....for about a week.

now when I heel toe downshift hard at all, the thing loads up & tries to die on me.
If I put it in neutral & give it a good rev it clears out (ton of black smoke) & runs like nothing ever happened

I'm not sure its the head temp sensor cuz its acting a lot differently than the last time.

I'm getting REALLY frustrated with the electronics on this thing.
if this keeps up I'm just gonna carb the damned thing & deal with it running shitty when I take trips to different evevations.

anyway. anyone have any ideas?

it has new grounds, new head temp sensor, newer cap, rotor wires & plugs

thank you in advance!
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blitZ
post Oct 9 2007, 06:31 AM
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Beer please...
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You didn't say which injection you are running, Ljet or Djet. There are injector grounds under the intake plenum, which can cause problems on a Djet. You can see them looking in from the passenger side. Also, check to see if your MPS holds a vacuum. May need to adjust the throttle position sensor.

I know it's a pain, but once you get it sorted the old injection is not bad.

Lots of good info here: Banders Djet site
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toon1
post Oct 9 2007, 09:43 AM
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The CHTS is only for warm up ,after the engine is warm, the system ignors it. If the CHTS is bouncing back and forth within the relm of reistance that the F.I brain notices it, it could cause this prob.

A faulty ground should not ruin the CHTS, they are internaly grounded.

Heat maybe causing it to go bad.

Have you checked the CHTS to see if it's bad?

have you checked the MPS for vac?
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BMartin914
post Oct 9 2007, 01:33 PM
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You need to got hrough the FI component one by one, testing them to determine if they are withing spec. This is covered in P.B. Anders web page. Print it. Sleep with it under you pillow.

These systems are quite simple, and run very well when in working order.

Don't throw parts at it. Determine whats good/bad. Replace the bad and move on from there.

Carbs are a half-assed solution for those who can't/don't want to troubleshoot a problem. It's over 30 years old - prepare yourself for trouble-shooting.
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SLITS
post Oct 9 2007, 01:51 PM
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D-Jet system ......

Same basic thing happened to me in Moab this year ..... it was the MPS.

I had put a "rebuilt" one on that I really didn't trust, so I carried a known good one. It ran fine all the way there. On Sat, when we were pulling out for the drive, the car started loading up and wouldn't run. It finally died and wouldn't start. Changed MPS and everything was okedokey from then on. I suspect the electronics inside took a crap.
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mike souza
post Oct 9 2007, 06:54 PM
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thanks for the ideas guys.

a few questions:

BMartin, who is PB Anders,& what is his web page?
its a stock 75 1.8 inj. system is that d or l-jet?
what/where is an mps?
also what is the best literature out there on 914 injection sysems? Any good books I should buy?

most of my frustration is coming from the fact that I'm an idiot when it comes to electronics.
mechanically I can pretty much do anything I need to, but as far as I'm concerned fuel injection works on magic haha

& yeah, the idea of converting to carbs might be a little half assed, but I know damned well that they wont ever burn out a damned relay (IMG:style_emoticons/default/barf.gif)


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jim_hoyland
post Oct 9 2007, 07:21 PM
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Get that VIN ?
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Mike,

It might be helpful if you post a couple of pictures of the engine. We can then see what is still hooked up --hose wise. The sigle biggest issue for me was tracking down and eliminating vacuum leaks.

I have 1.8 L-jet and went through a bunch of issues too; this is actually a workable system. Post up the pics so we can see what's there...
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