Jon_Valjean

Apologies if this is obvious, but by "ground straps" do you mean the earth cable from the battery to the chassis, or the earth cable from the actual engine to the chassis?

P'cola FD

Both

rx7speed811

****, i brought my car into the shop yesterday. it sounds like my rear rotor is not reading well in the compression test

P'cola FD

That sucks, but look on the bright side, now you can port your engine.

rx7speed811

yeah, it is two blown apex seals in the rear rotor. but the motor had only 12000 miles on it! i think i had a lemon motor, my pfc fuel settings were already set way above what i needed for the boost i was running, so i dont think it was that. my previous mechanic who ordered the motor for me is talking to the company about warranty issues. wish me luck.

have you found your problem yet?

silikenrf

P'cola_FD,

I changed the wiring harness and now have a hesitation on the front end. Need to feather the gas just to get it going, but when it "catches" she run's like a bat outta hell. I am going to take the plenum back off this week and check around the vacuum hoses (probably swap the 93 plenum for a 94 that I have access to which matches the wiring harness). There are such small subtle differences between the 93 and 94, but it seems that I am missing just one thing. If anyone has seen this "feathering" thing (as long as you DON'T let off of the pedal you can drive around town, as soon as you would let go to shift, its back to feathering) please let me know.

P'cola FD

I used Rodney's coils, coil harness and wires and nothing changed. Which leads me to think that it is either injector or wiring related. I will pull it back apart in a few days and see what I can find.
About the wiring, how can I check for shorts? I don't know the proper procedure and haven't been able to find an explanation on the net. Also, what wires should I check? Thanks a lot.
--Danny

silikenrf

too much wire to "ohm out" - even the oil has resistance that is measured (believe it or not). A new harness is $680 dealer price (they get it for $4??) retail is $8?? Its a bear to get out, but at least you can rule out electrical wiring.

P'cola FD

I was considering a new or slightly used harness, but if I can find and fix the problem with mine I'd rather do that. I have a pretty good Idea, but what is required for a wiring harness replacement? Does the engine need to be pulled? Silikenrf, how long did it take you, and the $680 for the harness, is that at a discount? Because I work at a dealership and can get pretty good deals on parts.

Anyone else know how to troubleshoot the wiring harness?

rx7speed811

i think to test it you have to tap in and check each individual wire to each sensor. i didnt see a shortcut to testing the entire engine harness in the service manual.

just curious, how has your compression for each rotor chamber checked out? i had no clue it would be my apex seals when i was diagnosing the problems i was having.

P'cola FD

I had 120 psi on both rotors. That was my first idea. I always suspect the worst first.

P'cola FD

I pulled the UIM and solenoid rack out and I think I might have found my problem. The outer shell of the connector to my #1 rotor primary injector is broken off, but the inside part with the female connectors is intact. Although it seemed to be slipped up a little, not off, but a little. The rest of my wiring harness looks pretty bad, but I would rather not replace it if I don't have to.
How much more work is it from where I am?
Does anyone have a harness in good condition for sale?
I will replace the connector if possible, where can I get a connector that will fit?

P'cola FD

Also the single wire water temp sensor's wire broke off at the sensor. That is to the fans though so I doubt it is the problem.

silikenrf

P'cola_FD,

It took more than the wiring harness. The harness had to be MATCHED to the plenum. I had taken a ported '93 and put it into a '94 using the '93 harness initially and it behaved as you described. I then replaced the harness with a '94 (yeah its $680 dealer price), and redid all of the vacuum, but the reverse started happening (no bottom and great top end). We then put a '94 plenum on and put her back together and VIOLA, she's humming. The harness is a 1/2 day job for the experienced.

I am now trying to figure out how to bring the boost down from 15 to something reasonable. This car is too fast!

Greddy IC
Larger Injectors (porting and injectors balanced for stock ECU) really needs the AEM
Mid and downpipe (way too loud)
Advanced Designs suspension

P'cola FD

What condition is your 93 haress in? If it's good I might buy it, if not, could I get a few connectors off of it?

silikenrf

P'cola FD,

I wouldn't trust any 9 year old wiring. Contact Jerry at http://www.cleanandfast.com. He may have the odds and ends that you need - he also has the '93 harness.

brads

hey man,
just wanted to let you know, the same thing is wrong with one of my secondary injector plugs. it hasnt caused a problem yet, but i believe it would still be worth a try in your case. let me know if i can help out in anyway. i dont have to be at work until 3:30 all next week.
good luck,
brad

Tim McCreary

PCola,

There is a new harness on the parts trader for $400. NEW. I just saw the ad.

Good Luck
Tim

http://www.thepartstrader.com/Single...=101&C2ID=1004

P'cola FD

IT'S FIXED!!!
The connector must have just wiggled up enough to hop on and off when it wanted to. I replaced the connector with some spade connectors until I can get a really one. I still seem to have a boost leak, but that doesn't matter right now. I can actually drive my car around. Woo Hoo. Thank you God!
I really want to thank everyone on the forum that helped. I supremely appreciate all the help that you guys have given me. Now the question at hand is, who do I give the money to. Dale Clark is the one who told me that it could be my injector not opening up on the #1 rotor fron a short, but he's not on the forum. I looked back over all of the posts and no one was really headed in that direction. I might give the money to Dale, unless I can get some sort of majority agreement from you fellas on who should get it(please let's be civil).
--Danny

stevecod

what connector are you excatly talking about?? i need more info. i have the same problem.

thanks, steve

P'cola FD

The connector to the primary injector on the first rotor. The plugs on the #1 rotor looked shiny like they were fouled, but the rear rotor plugs looked normal. Power would not come on until after 3,000 rpm when the secondaries came online.

rx7speed811

if you were to continue driving with the messed up primary injector wiring connection, would that be a probable cause for blown apex seals in the rear rotor? i just want to know so i can be safe when i get the new motor put in.

rx7speed811

is there any way to test that connection electronically without the car started?

P'cola FD

I don't know of any way to test it other than using your eyes. It could definitely pop a motor, because your motor isn't getting enough fuel.