Carrera doesn't want to start

[GSpreeman]

I turn the key and the starter kicks over fine but the engine just doesn't really want to start like it used to (nope, didn't do anything to it). What do you guys think? Plugs? Wires?

[nostatic]

check to make sure the fuel pump relay is tight in its socket. That kept mine from starting one day, and is an easy fix.

[GSpreeman]

It does start but sometimes I even have to pump the gas pedal once or twice. Could that be the fuel pump relay? If so, where is the thing? Under the driver's seat?

[nostatic]

no, if the pump relay is out, it won't start at all. It is located up front in the fuse panel...its one of the big round relays along the top row.

[GSpreeman]

That's not it then. Either it's not enough spark or the mixture is wacky. I'm still getting like 10mpg so maybe it's too rich and has fouled the plugs or something.

[Jim Smolka]

To see if the Fuel Pump is working, have a friend start turn the key while you listen for the pump. It should be behind the gas tank near the brake MC.

If working alone, remove the 19mm fuel rail cap nut on the back of the engine drivers side. Be sure not to loose the small steel ball inside of the nut. Catch the gas with an old spray bottle top. Then connect a hose to the fuel rail. Place the other end of the hose into a suitable container. Start the car, note if any fuel is coming out the hose.

[Rick Lee]

Guys, this is a Carrera. I think the only "fuel pump" relay is actually the DME relay, which is located under the driver's seat. I had this exact same problem. Turned out to be a dead fuel pump, but you'll need to try a new DME relay before you start troubleshooting. You can straight-line the fuel pump off the battery by running a thick wire from the fuel pump fuse terminal to the flasher fuse terminal - I forget which one goes to upper and which to lower. But since the flasher circuit is always hot, if you run a wire from it to the fuel pump and hear it whir back to life, then you know it's not the fuel pump. In my case it coughed, stumbled and the wire got orange hot, so I knew it was time to replace the fuel pump.

[BGCarrera32]

A simple test to confirm fuel pump operation...

- Ignition off for these tests
- Connect a jumper wire to Fuse 16 in the trunk fuse panel
- Touch the jumper to Fuse 17 in the panel. The fuel pump should run.
- remove the DME relay (under drivers seat, next to the Motronic brain)
- jumper pins 30 and 87b - pump should run

Ignition On
- DME relay pin 86 should have battery voltage
- DME relay pin 30 should have battery voltage
- DME relay pin 85 should have ground

If all these tests are good, the pump and pump control relays are good.

Your pump will not run until the engine is cranking. I find this annoying on these cars...a lot of efi cars you can turn to run and the pump will operate to build pressure or "prime" the lines. No go on a Carrera, they have a check valve right off the pump that maintains hot restart pressure to something like 14 psi?...is your "no start" a hot or cold engine issue?

-BG

[old_skul]

It's the coil.

[GSpreeman]

Thanks guys. I'll be playing with it this weekend. Perhaps I'll keep the fire extinguisher close since I'm playing with fuel, jumping fuses, etc.

[Lorenfb]

Did anyone think to check how strong the spark is?
Pull the coil wire from the distributor. The spark should
jump about 20-25mm to the alt. housing.

Also, "pumping the gas" doesn't really work on Motronic
type engines like carb engines.

Check out the website (systemsc.com). It may have some
useful info for this problem under Diagnostics.


Good Luck
Loren
'88 3.2

[Steve W]

Check the infamous failing DME relay under your seat. When it begins to fail, sometimes it starts, sometimes it doesn't and over time it gets worse. You could do a quick check by listening/feeling the relay as you turn the key, it should click. There are two relays inside. One energizes the DME, the other powers the fuel pump. They operate sequentially, where the first relay powers the DME when you switch on the ignition, the second when you turn the starter. The problem with the relay is the poor solder joints inside the relay on the circuit board. The cantilevered load of the relays inside standing horizontally place stress on the solder joints, eventually producing hairline cracks in them. You could attempt to resolder the relay's solder joints, or just buy a new one and if it's not the problem, keep it as a spare when your old one goes bad.

[ischmitz]

Wait,

if it stumbles to live and runs poor it could point to flow restriction in the fuel (fuel filter) or weak sparks (coil, wires, plugs). If it cuts out all together that could be the DME relay. The fuel pump relay is easy to check: While you crank someone else listens to it. Try the simple things first. (Fuel filter, check wires).

BTW: I saw that you can fix the DME relay yourself if you are friends with a soldering iron. It's the solder joints on the PCB side going brittle over time on a batch made in Hungary. Just resolder and save yourself some bucks.

10mpg seems pretty low. Was that ever since the case or did it happen gradualy? Are you driving it like you stole it?
Ingo

[targa911man]

I tend to agree with Ingo. I doubt it's the DME or the fuel pump. The pump is probaby working if you're getting enough gas to the cylinders to get 10 mi/gal. The combination of starting/running symptoms coupled with the low gas mileage makes me suspect something closer to the combustion point on either the fuel or electrical side. I've had various DME relay problems, but none tha match your symptoms.

[GSpreeman]

I'm not driving like a maniac. Most of the time is spent going to and from the store...35mph, 2nd gear, 3,500-4,000rpm. On the last tank full I averaged 11.4mpg. I need to change the plugs, wires, etc. but still, the sluggish starting combined with fuel consumption is a bit odd. Can I take it to a shop and have them diagnose if the car is too rich, etc? Should the DME be controlling that already?

[makaio]

When was your last tune up? You know plugs, cap, rotor, fuel filter, etc..

Sounds like you may be due.

[ChrisBennet]

BG,
On my '86, the fuel pump fuse is something like #7 if you go by the #'s on the fuse box lid. #1 is the fuse closest to the "skinny end" of the fuse box i.e. closest to the driver/rear of car.
I run a jumper between the bottom of #7 and #6 to force the fuel pump to run.
-Chris