I have a 1989 744GL with 140,000 miles. B230F with LH 2.4 fuel system.

I've reciently been having cold start problems. The engine always starts but runs very rough like its running on only two cylinders. I step on the accelerator to bring the RPMs to about 2K and the engine smooths out after about 20 to 30 seconds. There is usually a strong smell gas as I back out of my garage. The car run well once I get passed the cold start. Warm starts (15 minute cool down) are always fine.

Reading all the helpful info on this site, I decided to clean the throttle body (TB) and also replace the ECT Temp Sensor. I got home from work, let the engine cool down for a couple of hours, and then removed the TB. It looked pretty clean. I then notice a puddle of fuel in the bottom of the intake manifold!! I would guess about a 1/2 oz of gasoline. Could this be my cold start problem?? Why would fuel puddle there? Leaky fuel injector?

I haven't put it back together yet so I don't know if changing the ECT Senor is going to make difference.

Has anyone come across this before?? Please advise.

thank you,

Bob

I understand there is a Volvo service bulletin to render the fifth injector inoperable.

An 89 should have a cold start injector screwed in the floor of the manifold. Pressurise the fuel system with the throttle off and check for dribbling out the injector. The main injectors would dribble onto the valves. The regulator could do it but they usually put out enough gas the car won't run at all.

To pressurise, remove the f.p. relay and run a jumper from power to the heavy yellow wire which runs to the fuel pump. Let the pump run and watch the injector. Do not crank the engine as it may start and rev to the limiter.

Remove the vacuum hose between the fuel pressure regulator and the inlet manifold, dribble of fuel = new regulator

Regards

Bob:

How about a leaky injector or a bad fuel pressure regulator booth items can caused the pudle of fuel.

Does this a self diagnostic box on it? My 89 240 does.

Two thoughts.

1-(unlikely) Sounds like the temp senor. You may have put in a bad one or put it in wrong. But a bad one would cause the car idle fast even when hot. Check it with an ohm meter.

2-(likely) While cleaning the TB, did you remove the TPS (throtle positioning senor). When I cleaned mine (240), it would do the same thing. Idle high and then be fine at normal temp. If you removed it, reposition it.

OR in my case also, I tighten the throtle linkage nut too much. The trotle would be slightly open when I would start it, confusing the car and return to normal after I rev it up and when hot. Remove the throtle linkage from the TB and start it then. See what happens. If still high, turn the TPS clock wise (if you removed it) untill it idles fine.