So, I’ve started a new employment just a couple weeks ago which means I’m exposing my old ’99 Saab 9-5 to a lot more trouble than it’s used to. Instead of a 10 km morning and evening ride, I’ve increased the daily rides seven fold; about 75 km each morning and evening.

A few days into this new ritual, I got a flashing engine fault signal on the dashboard, and I immediately hooked up my fault code reader. The response was a pending 1312 (I think), and as my app couldn’t (or wouldn’t) resolve that error code for me, I googled it. Well, I usually google the error codes anyway, to get all aspects and views on the fault.

As usual, I got a lot of input. It’s always nice to see how huge the interest for these old cars are all over the world.

Anyway, the 1300 error code appears to be (well, the evidence is rather conclusive) engine misfiring. Getting the 1312 appears to mean that cylinder one and two are the ones misfiring. 1334 would, per that logic, mean cylinders three and four. A blank 1300 (flashing) means that the misfiring cylinder could not be determined.

So, I bought four new spark plugs and installed them today. A have noticed that two of four screws holding the ignition package in place has been missing for quite some time. Ignorantly I’ve failed to fix that, not knowing that these actually holds the connectors for the spark plugs in place. The two remaining screws had also come loose, and on top of not having replaced the spark plugs for God knows how long, the left side – corresponding to cylinder one and two – had probably gotten a bit too loose. Perhaps road vibrations would cause bad connectivity for spark plug one and two.

Anyway, after replacing the plugs, the engine seems to run much more smoothly and quietly. Granted, I haven’t taken it for a test run (since yesterday evening was the annual cray fish fest, and those buggers ban car driving all the following day), but idle seems much more smooth now.

Also, the last month or so, I’ve noticed an increase in fuel consumption. The lowest I’ve been is about 6.9 per 100 km, and now it’s on 8.1. Perhaps that will decrease now as well.

Oh, I just noticed I hadn’t put any text into this post. Sorry for that. I found out, actually, noticing someone had specifically requested this post, probably to find out a little something about the fault code P0116. All he got for his trouble was a Hello world message.

So I thought I should write something from my experiences with this fault code, rather than just delete the post.

I first encountered the fault code P0116 on out Saab 9-5 Biopower, an 2006 model with 250.000 km on the meter. I later saw it on a neighbors Saab as well and even on my bonus father-in-laws Saab, so I think it’s a common enough error code on older Saabs.

Googling it led the quite a few tips, the best one I didn’t follow immediately, but should have. It read something line:

This error is raised either because of a faulty coolant temperature sensor or an old, tired thermostat. As each is like $ 15 and it’s always going to be the one part you don’t replace that’s faulty, it’s best to change both at the same time.

This turned out to be the best advice I didn’t follow. I only replaced the sensor, and a few days later the engine light turned on with the same error code.

A while later, I changed the thermostat as well, and the light has stayed off ever since. After the new thermostat the coolant temperature behaves much better as well.

I changed the thermostat on my neighbors car as well a month ago, after she had had the shop replace the sensor three (!) times. Same problem with weird coolant temperatures before the replacement, good behavior and no engine light after the replacement.

Changing the sensor takes 20-30 minutes, changing the thermostat takes about an hour, so I think the benefit of replacing these two items definitely outweighs the bother and cost doing it.

The Saab Engine Code P1110 – Charge Air Bypass Valve.

This fault conserns a fault in connection control hoses (see picture) in the solenoid valve or in the bypass valve.

Fault criteria

• Charge air pressure pulsating at 14-18 Hz with amplitude exceeding 3 kPa. Criteria must be fulfilled on two separate occasions within 600 s during the same driving cycle.

Enable criteria

• Atmospheric pressure must exceed 72 kPa and the engine coolant and intake air temperatures must exceed -7 °C
• Main relay voltage exceeding 10V. Engine speed below 3500 rpm. The inlet pressure drops rapidly by more than 3 kPa whereupon the accelerator pedal is fully released. The charge air pressure exceeds 120 kPa. The solenoid valve for the by-pass valve has been deactivated.