runs crappy when cold

Roastin944 · 12-16-2002, 07:21 PM

When i first start my car even when its not completely cold outside, just after it has completely cooled down and sat for like 5 hours, it runs like crap, it does not want to warm up for a while, when i hit the gas, it kindof stalls or doesnt want to respond to the throttle at all. Also until it warms up it has that ripping sound that all hondas have, it sucks! Hondas sound terrible! I think that might be from my high flow cat. Could the crappy running be the O2 sensor? Or is this normal? I also heard hooking up an air/fuel gauge can make it run worse, any thoughts? Thanks alot

John

AaronM · 12-16-2002, 08:07 PM

I'm rather new to the 944/924S but I've become rather familiar with older BOSCH FI systems after dealing with my 914 and my sister's 320i. The older BOSCH FI systems are, unfortunately, not like the PGM-FI that Honda used, and the BOSCH FI has a history of not liking the cold.

My 914 has always needed a gentle throttle foot on the rare occasions that I move it around in winter, and my 924S needs to build some heat before I can do anything really aggressive with it. That's as it should be though, since it's far from wise to rev or load the engine when it's cold. Until the engine is at operating temp, you really shouldn't rev it past 3,000 RPM or put much load on it. Basically, drive like a granny until the engine's warm. Once it's got some heat in it you can drive it like you stole it though.

Unless you are having severe problems on a cold start (like it's stalling or bucking heavily) or your ambient temperatures are in the 60's or higher, I wouldn't worry about it.

Aaron

Magnus_944 · 12-17-2002, 03:38 AM

A well working bosch motronic system is fine in cold weather, my 944 starts easy and idles well in -10 C. The old and nasty D-jet system on the 914 and other older cars is probably a different thing. (some people call it "the doomed efi from hell"...)

I think you have a sensor problem, my first guess would be the temp sensor.

//Magnus

Roastin944 · 12-17-2002, 01:49 PM

well it runs fine in cold weather....once it warms up. The outside weather temp doesnt affect it much, its what temp the engine is at, it runs crappy when the engine isnt warmed up, although even worse when it is cold out....but still not very well when its warm out and i just started the car.

jseel · 12-17-2002, 02:55 PM

my 951 runs really bad when the engine is cold,worse if its really cold. my volvo 240 is much faster out of my driveway. i live on a busy road and the lack of power when cold is dangerous sometimes. it also stalls if you arent really careful with the clutch. all this only lasts about 3 minutes or so.

AaronM · 12-18-2002, 09:54 AM

Quote:

Originally posted by Magnus_944
A well working bosch motronic system is fine in cold weather, my 944 starts easy and idles well in -10 C. The old and nasty D-jet system on the 914 and other older cars is probably a different thing. (some people call it "the doomed efi from hell"...)

I think you have a sensor problem, my first guess would be the temp sensor.

//Magnus

My 924S starts and idles fine in cold weather (17 degrees F), but until I've got some heat in the engine the car just doesn't accelerate as strongly as it could. My Honda could be floored right after starting in this same weather and it pulled every bit as strongly as it did when warm, no car I've ever driven with an early BOSCH FI does that. 914 starts and idles fine, but it also lacks power when cold. Same with my sister's 320i (K-Jetronic). As long as the car isn't stalling at idle, you're probably fine. It's a shame that the BOSCH system in my car doesn't blink error codes via an LED like the old PGM-FI in my Accord did.

Aaron

seb928s · 12-18-2002, 04:43 PM

Quote:

Originally posted by jseel
my 951 runs really bad when the engine is cold,worse if its really cold. my volvo 240 is much faster out of my driveway. i live on a busy road and the lack of power when cold is dangerous sometimes. it also stalls if you arent really careful with the clutch. all this only lasts about 3 minutes or so.

My 951 does the same only when it's really cold it will start right up and it will have a hard time getting going fast I never take it over 3000 rpms while it's doing that and it last about 1-2 minutes, but I never had it stall.

Makis · 12-19-2002, 01:23 AM

Quote:

Originally posted by Magnus_944

I think you have a sensor problem, my first guess would be the temp sensor.

//Magnus

Would agree with this one. If the sensor sends the wrong signal then the Bosch engine management may think the engine is warm and uses a weaker mixture then necessary, causing driving problems. When the engine warms up the sensor may record signals closer to the true engine temperature and hence the car drives OK. If your car was an S2 then this could be a good reason. I think the standard 944 have something called cold starting valve? It may be something to do with this valve not working properly?