940 (1994) fuel too rich? weird issues also between 2 cars

wintersun · Post by **wintersun** » 31 Oct 2009, 19:37

OK: first off, I'm Summer and I love volvos. We've had at least 12 of them in my lifetime between me, my dad and brother. Most recently, a 1988 740 with a 5.0 Mustang conversion. Fun while it lasted.

I just bought two 94 wagons, one with a "bad transmission" and one running, with 155K. Wasn't planning to buy the 2nd one, I was just going to part out Car#1 and get my money back.

I was helping out some friends who'd planned to scrap the bad tranny (car#1) car and were leaving town short on gas money. I figured I'd part out the engine and tires which were nearly new. Then my dad saw the other car, I have a 15 year old daughter, and a match was made.

Until I broke down in the running car. Fuel issue. Changed out the filter, no go. Top end of engine has been "rebuilt". Okay, the car was cheap enough and we have a donor, so we figure it'll be all right, we're mechanics, we won't be into the thing for labor. 155K miles. We'll pull the good parts off the car with the bad trans (maintained perfectly for 150K miles, then driven into the ground to 187K) My bet is on a fuel pump relay which I had issues with on my 88 740 wagon but my brother's against me on it.

Get both cars beside each other and the engines looks completely different. distributor caps on opposite sides of the compartment. Air flow sensors don't match up. Fuel pump setups don't even seem to match. Which fouls my plan to switch out fuel pumps and relays to help diagnose my fuel problem in my semi running wagon Car#2. (which will catch but not idle--too rich?)

My dad says he solved it- Car#1 with the bad tranny has a CA emission sticker on it (was bought in Atlanta) and he thinks bc it was a metro car it has a completely different emissions/fuel injection system and therefore the top end is constructed differently.

do ya'll agree?
If I put up photos of Car1 and Car2 would you be able to look and say HOLY CRAP that's the engine from a 240! or something like that?

Was there a mid-year design change or something I don't know about?

Post by **billofdurham** » 01 Nov 2009, 12:18

Welcome to Matthew's Volvo Site.

If the fuel is too rich I can't see how changing the fuel pumps and relay will sort it out. Usually when these items go wrong you will get no fuel.

Has the car thrown any fault codes? This is a first step in diagnosis which you can do yourself using the On-Board Diagnostic (OBD) unit.

The only change to the 940 that I can find for 1994 was the introduction of a turbo model. Cars for the Californian market did have a California emissions package but I don't know that it would change the engine layout so much.

distributor caps on opposite sides of the compartment

The distributor for the 940 is on the rear of the engine.

Let us see some photos as this is interesting.

Bill.

drsugg · Post by **drsugg** » 01 Nov 2009, 14:25

Well you have a Calif legal 940 and what we call a 49 state 940. Main difference is that Calif 940 is a motronic fuel system and the 49 state is the old LH system. The motronic incorporates the ignition and fuel controls in one ecu. The 49 state uses a LH system for the fuel injection,with the Regina ignition system on the side. Why? beats me. I prefer the motronic myself.

Post by **billofdurham** » 01 Nov 2009, 15:16

Thank you.

I have often wondered what the differences were. In the UK we have one set-up which may not be the best, but it certainly makes life easier.

Bill.

wintersun · Post by **wintersun** » 01 Nov 2009, 15:45

we're taking photos right now and we'll have them up in a few. In the meantime, can someone remind me about an rmp sensor wire I should look at? I saw mention of it somewhere in a thread from 2005. We've switched out relays from working cars and that is not the problem nor is the pump.

stumped,

Summer

wintersun · Post by **wintersun** » 01 Nov 2009, 16:18

Photos:
From Cali

From FL

wintersun · Post by **wintersun** » 01 Nov 2009, 16:20

I mean, there are other differences like I said, coils are on opposite sides of engine compartment, MAF is altogether different setup, etc and I can do some more photos tomorrow in the daylight but was just wondering if anything about the setup you see here is a dead giveaway.

Post by **billofdurham** » 02 Nov 2009, 12:51

I'm going to stick my neck out, and will probably get it chopped, and say that the engine in the Florida car is not from a 940 nor a 740 as the distributor should be on the rear of the engine. The 240 had the distributor mounted on the side.

Bill.

wintersun · Post by **wintersun** » 02 Nov 2009, 13:43

OK, two things:

1) this car has a cap on the rear of the engine where a distributor was or could have been, and has been capped off. Theories? Ideas? You'd have to see this car to believe it- I mean, this is a factory switch if it's a switch. The entire wiring harnesses are professionally switched. This isn't some garage quick switching out an engine. coil positions, everything. We can't figure out why it was done, but looking it at it it feels like it HAD to be done on the Volvo line. I could post better photos of the engine compartment if anyone is interested.

2) Our immediate problem, the fuel issue. Can anyone help us nail down where the crank position sensor is, or whatever version of this the volvo uses? RPM sensor wire, etc? My dad feels sure that there is a mis-communication happening between the fuel pump and the crank sensor. relays all check out. fuel pump pressure checks out.

Post by **billofdurham** » 02 Nov 2009, 15:35

The 2.3 engines for the 240, 740 and 940 were the same, B230F or FT for the turbo version, and were introduced in 1985. The blocks and heads were the same but some of the ancillary equipment was different. A prime example was the distributor. On the 240 it was mounted on the left side front of the engine, on the 740 and 940 it was mounted at the rear of the engine. Whichever hole wasn't used was blanked off at the factory. If you look at the left front of the CA engine you will see a blanking plate where the 240 distributor could go. If the engine was changed by a professional he would make sure that the coil and other parts were put in the right places for that particular engine.

The crank position sensor, also called the impulse sensor, is mounted on the top of the bellhousing at the rear of the engine. It was a problem area on some of the earlier cars as the insulation was prone to wear.

Have you checked for fault codes as not all codes will light up the check engine light?

Bill.