My 740 gl recently started having start up issues after driving, would stumble and miss and then clear up and run ok. Check engine light came on, ran onboard diagnostic code 113 came up, injector issues. Bought injectors from ipd installed them and it ran worse. Did another diagnostic and codes 121 & 322 came up, MAF issue, bought a new MAF from ipd and when I can get it to start runs like crap. Was told by old Volvo mech. that I might have to drive it 30-40 miles to allow reset fi control unit, would if I could it won’t run that long. Help- any ideas ?

Change your ignition switch. High mileage pitting. I did see that your ground wire was not tight.....If your start having problems again go for replacing the switch.

I was also told that a new sensor in one of our 740s that the computer would need time to set itself.

Volvos compensate for problems until they become so bad that the car is in trouble.

I was told that start-ups were important as well as mileage.

I am sure that you are getting good advice - but - even though your car is giving you trouble from new parts - keep trying unless you find other issues.

I do not know about today, but in the past, I never had a dealer tech replace ore than one part to correct a problem.

Most dealers will not charge you more than one hour's labor to find a problem.

This may be an industry standard, as my son-in law tells me that Subaru has the same policy.

Thanks for the moral support. I did get a new code 223 for the idle control unit and ordered it from ipd. Obviously you don�t live in Hawaii, here they seem to want to just empty your wallet. Thank you again, Gordy

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Hi Gordy,

Have to be careful when interpreting the codes. When codes appear one after another should start suspecting the ECU itself (water ingression?), ECU connection (oxidised connector pins) and the engine item thats connected to it ie. the idle valve (for code 223) could be stuck, dirty or disconnected. Rarely the idle valve was found to be damaged. Another example would be code 113 could also mean intake manifold gasket leak, leaking throttle body gasket, air leaks into old/loose vaccum hose and such. Replacing the injectors didn't work.

As you see, the codes need further analysing rather than try to pinpoint a fault.

Amarin

Thanks for the moral support. The car now starts and runs up to about 2000 rpm semi smoothly, above that it really starts to irregularly miss. It will run like that for awhile then die and not restart until it completely cools down, at least I think that�s why it will restart. Don�t have a dealer on this side of island. Many thanks, Gordy

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Since I just read about cooling down and then starting, that would be the ignition amplifier located on the drivers inner fender near the battery. The heat sink paste has dried out and causes the symptoms.

High mileage .......I replaced my ignition switch.....same thing was happening to my 1988 745t. Ignition switch contacts were pitted and not transferring 12volt power. I was chasing this problem for some time. Your car will run so much better once this switch is replaced. I accessed my switch by removing two screws that hold the dash instrument panel on. A little tight working area but, using a long straight screw driver bit and a 1/4 inch box wrench and duct tape to hold the bit you can get the switch out. I used a mirror and flash light to see the screw position.Be patient and place a cloth rag under the switch to catch the small screws. It's a three handed job. 🙏🙏🙏

Thanks to all for the input, after replacing injectors, MAF,and IAC it turns out a ground wire didn’t get tightened properly. Definitely my bad. Runs like a top!

I remember my mother-in-law’s 89 740 displayed the same sort of problem - running worse the warmer it got. Turned out to be a bad coil. You might try swapping in a known good one just to see if it helps.
Do you have a timing light that you can use to “watch” the ignition firing?

Just to inform that NOT all MAF created the same as original especially the aftermarket ones. Look into your new MAF's air pipe. Shine some light to inspect inside. I'm sure there NO any platinum wire there, replaced by some new age thermo-sensor. Look into your old MAF to compare. Aftermarket MAF uses thermo-sensor, thats why the price is lower. And thats why you got 322 code. Only the higher priced MAF from IPD uses the same platinum wire technology (granted its an old technology, same age as the car). To get rid of 322 code either use back your old MAF or get the proper MAF from IPD.

Might make sense but after installing new AMM and clearing codes it ran for awhile, really rough, and no check engine light came on, so rechecked codes, fi and ignition and both came up 111. Got it running again and same result. Still stumped. Many thanks for input.

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On the old OBD systems there are actually a lot of functions that aren’t monitored. At this point I think I would want to use a pressure gauge to check fuel pressure at the injector rail and also connect a timing light to confirm you’re getting a good strong spark on all four cylinders.

You should have LH 2.4 in your 1989 B230F. OBD code 1-1-3 on port 2 indicates a fuel trim problem at run speed. The engine is unable to vary the number of injector pulses and ignition timing to achieve the target mix as measured by the O2 sensor. With a B230F, this is much more typically a vacuum leak, fuel pressure/delivery problem or an O2 sensor problem rather than a fuel injector issue. In my experience, B230F fuel injectors are one step short of bullet proof. The O2 sensor may or may not be a problem in your case as it is only used when the engine has reached operating temperature and you say your problems were originally after a drive, suggesting a warm rather than cold engine. The note in the FAQ about injectors is for the Motronic fuel system.

Your subsequent 1-2-1 and 3-2-2 codes on port 2 do suggest an AMM issue, either a failing/faulty AMM or a poor AMM connection. One way to diagnose that is to disconnect the AMM, which puts the engine in limp home mode (and forces a 1-2-1 code), to see if the hard starting and rough running improves or changes. More often than not a faulty AMM results in a complete no-start. In my experience, a failing AMM (as opposed to a fried one) usually results in only a slight hesitation, not a bad misfire, coming away from idle, long before it starts setting any codes. The missing burn-off circuit suggests either a loose connector problem or a broken platinum wire (that should have created a complete no start), so your AMM may well have been fried if you at least tried to unseat and re-seat the connector on the old one.

The type of hesitation and rough running you describe followed by the engine smoothing out once it gets going at speed is highly suggestive of an ignition problem, such as a loose/failing ignition wire, fouled spark plug and even a worn distributor cap/rotor. I've had close to those same running symptoms with just a single ignition wire not properly seated and making good contact with a loose spark connector, also a badly worn distributor cap.

My undertstanding is that the ECU adaptive function uses the last 15 starts after the engine achieved operating temperature and was using the O2 sensor. This allows fine tuning fuel trim to the programmed combustion CO and CO2 emmissions. IMO, there's no way you should have such hard starting and rough running just because the ECU hasn't adapted to the new AMM and injectors.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Fuel pump relay could be crapping
out. Check main fuses.

Dave, thanks for the quick reply. I�ll see @ an 02 sensor tomorrow and check for any vacuum leaks. After getting the 121 & 322 codes I checked the AMM & the intake side was almost clogged w/crud. I cleaned it to no avail & so replaced it. The car had been running lean, according to the spark plugs, so I thought it likely that a clogged AMM w/old injectors might have been responsible for that, ergo new injectors. Will look into
Wires, cap, and rotor tomorrow also, with fingers crossed. Would you mind if I kept your return email just in case ?
Sent from my iPad. Aloha, Gordy
Not sure @ learning prev. 145/544/122/242/740T,740gl

Replace the knock sensor that exactly was what my 89-745 did

Please reply here on the brickboard forum rather than my email. That way others benefit from our discussion and add to the discourse. More importantly, it’s those who have more to contribute. It’s not like I'm an expert, just that I’ve been following your types of problems seemingly forever, both with my own bricks and those of others also here. We learn from each other!
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now