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Posted by: driver66 Jun 28 2003, 08:23 PM

damn car, I was cruising and happy,then i developed a miss in my1.7. so I kept driveing and it jumped out of it ,then back and forth. so I get home and throw in a new set of plugs and cap. [local parts store has the rest ordered] and fire it back up and off i go to work , no fix...so i figure its my injector cutting in and out. at lunch i wiggled some wires to see if it could be a bad connection . after work i jump in to come home and she would not do anything but turn over ,the fuel pump would not come on . so we pulled it in with a damn ugly s-10 and set ever sence......3 days ...............help me please find this problem

Posted by: Lawrence914-6 Jun 28 2003, 10:47 PM

To run, you need fuel, air (compression), spark and timing.

Have you checked to see if you have power to your fuel pump? What about the fuel pump relay?

Have you put your old parts back in, to check them? Just because a part is new, doesn't mean it's either the right part, or in good condition.

-Rusty

Posted by: driver66 Jun 28 2003, 11:07 PM

yes,ive got good spark in all cylinders. no fuel at all in the 3rd . and now no fuel pump at all. is there a relay or fusethat controls the individual injectors or 1 for all?

Posted by: driver66 Jun 28 2003, 11:09 PM

oh,an if the system is plugged would it shut down the fuel pump?

Posted by: tryan Jun 29 2003, 09:05 AM

if the fuel pump is not working, check the connection at the pump for corrosion, try a new relay or tap on the pump..

do 1.7's have the points for the fi in the bottom of the dizzy?


good luck.

Posted by: driver66 Jun 29 2003, 04:39 PM

i dont believe the points are in the distributor for the injection or maybe i dont know what im looking for. ive got no fuel at all. i cant get the pump to run and if i hook a jumper and make it run it dosent put no fuel threw to the injectors.....what the hell is this all 1 problem or 2???????????and the haynes manual isnt helping one bit.....

Posted by: tryan Jun 29 2003, 08:33 PM

the trigger points are in the bottom of the dizzy for the fi. it sounds like you just need a fuel pump relay or a small wiring problem. jump the pump for a second and start it. see if she runs on 2 or 3 or 4. if #3 injector is dead, swap it with another one to see if the problem moves with it.

Posted by: Dave_Darling Jun 29 2003, 08:36 PM

The pump is run by the ECU, which sends a signal to the pump relay on the relay board. Try swapping the two middle relays on the relay board with the two headlight relays in the front trunk. Then try the headlights. This will test the relays.

The pump should run for about 1.5 seconds when the key goes from "off" to "on". When the trigger points down in the base of the distributor open and close fast enough (showing over ~200 RPM engine speed, I think) the ECU will tell the pump to run.

The pump will pressurize the high-pressure loop of the fuel system. It will not cause fuel to flow through the injectors--the ECU has to tell them to open in order for them to inject any fuel.

First step is to get the fuel pump working. Check the relays, and check the wiring harnesses that are plugged into the relay board. There's a fuel pump troubleshooting chart on Brad Anders' 914 page, http://members.rennlist.com/pbanders . Chances are at least decent that you'll fix your other problem when you've fixed whatever is keeping the pump from running.

Then start checking all the basics.

--DD

Posted by: garyh Jun 29 2003, 08:46 PM

1) Does the fuel pump run when you first turn the car on? It should run for 5 seconds when you move to key to on. The center relay on the panel behind the driver's head is the pump relay.

2) If it does, is it making the correct pressure? (A -good- pressure gauge is $20. Everyone should have one.) 30~32 PSI, IIRC.

If the pump doesn't spin, it's an electrical problem, or a bad pump. If it does spin, but can't make pressure, it's a bad pump, a clogged fuel filter, or a bad pressure regulator. If the pressure is too high, it's a bad regulator, or a crimped/clogged return line.

Heck, it could even be a clogged screen in the bottom of the tank. (Which will eventually kill the pump. BTDT)

After you can say yes to 1) and 2) above, you can start looking for blown injector drivers (very rare), bad FI points (almost as rare) or clogged injectors (quite common).

A quick test for clogged injectors is to up the pressure to 40~45 PSI. If it starts running "better", you have clogged injectors. Do not leave the pressure that high; fix the problem, and set it back to normal.

Posted by: driver66 Jun 30 2003, 01:22 PM

dave; you nailed it .when i switch the relays the pump came on and the headlights went out.....thanks ,damn id have never found that.and ive not heard of it yet in any of my books.......gonna take her for a cruise and see if that doesnt fix all my fuel problems....thanks a lot gang..

Posted by: Dave_Darling Jun 30 2003, 04:21 PM

It's pretty convenient that all of the round relays are the same part. Gives you a number of easy ways to test them.

I also have all four sockets on the relay board filled, even though I don't have a rear window defroster. The fourth one is my "on-board hot spare".

--DD

Posted by: seanery Jun 30 2003, 05:13 PM

from a guy without a running car!!

Posted by: Curvie Roadlover Jun 30 2003, 08:12 PM

I was gonna say that. You beat me to it. Good advise, none the less. I have a rear defogger, but I'll do without it temporarily if I need a good relay to get me home.

Posted by: driver66 Jun 30 2003, 11:29 PM

the car runs good again ....thanks. well i wrote it in my cars log a little bit ago ...gotta grab some relays from somewere and finish my tune up....do you guys have a preferance for injector cleaner or what do you use ? I always have ran 93 octane ,so i didnt think this would ever come up as a potential problem