Barely starts & won't stay running

[Kevin81spider]

Hi everyone, I'm new to the forum as I'm also new to Spiders. Bought an '81 after selling my motorcycle. So far it has been a great running car, good power, no real issues to speak of. I had it on jack stands for the past month re-doing suspension. Go to start it up yesterday and it struggled just to start, once I got it running it sounded like a lawn mower, very rough as if misfiring and strong gas odor. I put 2 gallons of fresh 93 octane in today and pulled a plug - fouled! These plugs are only 3 months old. Cleaned them up thinking I found the issue but no change, it's running like crap. Need some advice on things to check. Thanks in advance!

[azruss]

I would start with electrical. check to see if you have a strong spark at each plug.

[rlux4]

We would have to assume that your car is an 81 by your user name. If that's the case you have a FI car. Do as Russ says, checking that each plug is getting spark is a good starting point. Also you should check that you have no air leaks in the intake system, mainly the boot from the air flow meter (AFM) to the throttle body, inluding the branch line to the auxilliary air valve (AAV).
Ron

[Kevin81spider]

Thanks I will try that. Why would the plugs foul so quickly? Very black, sooty deposit on all 4 plugs. What should I be checking once I get it running again?

[rlux4]

It's running way too rich, which is usually a problem in the FI system. The ECU will compensate for the signals it receives, if it receives incorrect signals it will control an incorrect amount of fuel into the engine. Air leaks become air entering the system that is unmetered, meaning the ECU doesn't know it's there and can't compensate for it. It could also be a problem with the temp. sensor in the coolant T. This is the most critical sensor being read by the ECU. If it's not decreasing resistance as the engine warms up the ECU will assume it's still compensating for a cold engine, giving a too rich mixture for a warm engine. There are a lot of mauals for the Bosch L-Jetronic system we have, but a good starting point is Brad Artigue's manual which has a section on the system. It would be good to study it to get a better understanding on how it works;
http://www.artigue.com/wp-content/uploa ... 124_MM.pdf
Ron

[giuliot60]

I've got an 81 as well that started running rough and fouling my plugs. Rlux and azzrus most likely have more experience that I do, so I would certainly follow their advice, but my issue turned out to be my temperature control sensor connector on the front of the engine on the "T". You can search for my thread from around August.

Also download Brad Artique's FI maintenance guide on mirafiori.com or from his site

[Kevin81spider]

Thanks for the manual and info, I will dig into it next weekend and check all sensors. Hope it's nothing too costly!

[giuliot60]

It's usually not expensive, just time consuming. My new TCS connector cost under $10 from Auto Ricambi. The good thing is that you will come out knowing a lot more about your car.

[wizard124]

I had a similar rough running issue. My problem was the connector at the air flow sensor at the filter box.

I had wrapped a split in the protective boot with electrical tape. This must have caused a short or ground issue. I removed the tape and it runs well.

[Kevin81spider]

Well I got the car running good again, have to say I feel kinds stupid. It was timing! Strange thing is that the distributor lock nut was not loose, why would it have changed just by sitting? Very strange but she seems to be running good. Finally got my front suspension upgrade finished so can't wait to get back on the road. I recently installed my short shifter kit as well. Thanks for the tips, I do still plan to check out my sensors.

[giuliot60]

Good news. But that is weird that the timing moved like that.

I would love to see what you did with the suspension. Did you take shots of the process?

[Kevin81spider]

I was bad about taking pics during the work. I replaced all the control arms, installed performance springs, and new shocks. Ended up with new rotors as well since they were too thin to have machined. Also replaced the stabilizer bar bushings and tie rod ball joints. Broke my brake fluid reservoir while doing some work under the hood so can't test drive it just yet. I'm also doing the rear suspension but going to take a break first and enjoy the car for a bit. Installing the springs was a major pain and just hope the rear is a little easier. Now that I learned the trick to springs I could probably do the job again in less than half the time.

[ga.spyder]

The rear springs are easier to do.Congrats on getting her up and running.

[Kevin81spider]

It's been a while since I was on the board, have been taking a break with the car work and just enjoying the drive for a while. Just put the car back in the garage to tackle the rear suspension and some brake work. The rear springs are so much easier than the front, once I let the rear axle drop I was able to pull the springs out by hand. However, I have a new question/issue. The right rear rotor was stuck, so I was rotating by hand and tapping with a mallet to remove it. All that went fine but later I noticed the entire shaft assembly was loose from the axle. I could just pull by hand and see the wheel bearing, seal and spindle. It seems when I pulled this out it should have gushed oil but there was none. Major issue or should I just top off and carry on?

[SLOSpider]

Kevin that is not good if you can just pull your axle straight out. It means the only thing holding your axle in was your caliper. There should be an internal snap ring that goes on the outside of the axle bearing. You will see a grove on the inside of the housing once you push the axle all the way back in. It may have broke or someone forgot to put it in. Fluid is kept in the axle housing by the seal so no fluid should have poured out but you should check you level and fluid anyways. If you don't know how old it is change it now.