Major problems! Need some help

[silversleeper]

So, I am driving my car and everything seems to finally be going good, and then I notice a slight hesitation when I accelerate in the low rpms. I think maybe she needs a tune up, and plan to do that sometime during the weekend. Then, last night, on my way home the car starts to hesitate really badly. This is after some spirited highway driving. I come to a red light, and my check engine light comes on as usual (it has been coming on at idle ever since I bought it, but I havent figured out how to check the codes just yet)

The light turns green, and I give it some gas to get going, and the car sort of bogs, and hesitates really badly. The two issues I have had ongoing for some time is that check engine light coming on only at idle (when rpms are lower than 1k) and the exhaust leak. When I drive though, it feels like the exhaust is the problem. My car struggles so bad to get up and moving, I feel as if during my highway driving, I caused the cat to spit out some of its internals and that chunk is clogging up the exhaust. I have not done any diagnosing yet.

I am thinking tomorrow I will change the spark plugs and maybe the O2 sensors. As far as the exhaust goes, I think I will try to pull off the catback and see if there are any major clogs. When the crazy hesitation happens though, the check engine light comes on at any rpm I am at, and starts to blink. And the car idles on its own when I come to a stop when it goes into this crazy mode. The car revs itself to 1500rpm, then to 2300 rpm, then up to 3000rpm, and fluctuated around there. I also smell a horrible smell. I think its the rotten egg smell associated with cats, but I am not completely sure.

Please excuse the length of this post, but I am trying to be as descriptive as possible. I am starting to wonder if buying this car was a good idea. I feel sometimes I should've stayed with the Honda family, motors I knew very well, cheaper parts, and more reliability. Please help me out people.

[Tangent]

Give the cat a solid tap (when it's cold!) and listen for rattles. If you hear alot of rattling there's a very good chance that the cat's come apart inside. $100 - $150 at any decent muffler shop and you'll have a nice new high-flow cat installed.

I'd also suggest looking for cracks/leaks on the intake between the throttle body and the AFM. Don't regret leaving Honda for your 325! There might be a bit of a learning curve and parts might cost a bit more but It more than makes up for it in how fun it is to drive. Don't be too sure about that reliability thing either, I'd be willing to bet that the average E30 easily lasts just as long or longer than any 1980s Honda. With the exception of the popular CRX I really don't see a whole lot of 80s Hondas on the road anymore, especially considering the numbers that were sold. Then compare that to the number of E30s that are still around.

[silversleeper]

i will try that tomorrow morning. did i mention i only get 16mpg?

[PeaveyBassist]

I get about 16 mpg if I drive around town and floor it all the time :) lol. It sucks balls. But if I accelerate slow and shift between 2.5k and 3k most of the time I get around 21mpg. I have a '91 325i btw.

Will

[RCWells]

That doesn't sound right at all Will. I get 21-22 and I don't drive easy. I actually avg'd 26-27 over a 3 hr trip doing 60mph (yes, that IS slow, but i was low on gas, and had no money) a couple weeks ago. You should definitely be getting higher mileage.

[Tangent]

Mileage-wise I average 22-23 in mixed city driving and ~80mph highway driving If I did less I'd get run over). I don't beat my car but I'm certainly not easy on the throttle either. Whenever I take it easy and cruise at ~70mph economy climbs to around 27mpg.

[silversleeper]

I just got back home again. The car drives super rough, just crazy hesitation throughout the entire rpm band, granted, it gets smoother around 4k rpm and up. But the hesitation still exists there too, just not as erratic. To give you guys an idea of what it sounds like, it sounds similar to a WRX with an exhaust, its got that rumble.

The check engine light came on during that 5 minute drive back home. About half way through my trip home, it came on steady, then went out and came back about three times in short bursts, but then went out again to never return. I dont know if that was a code, or just the check engine light flickering. It is too damn loud to test it right now, I fear my neighbors might complain.

I have a good feeling it is that cat though. I will pull off my exhaust (if i can, considering the major rusting of it) and see what I can clear out, if there is anything to clear out. Spark plugs will get checked next, followed by O2 sensors.

[DaN]

Is the exhaust leak before or after the o2sensor?
Did you check the rubber boot that comes off the afm? These are a common problem, they crack and allow unmetered air into the engine, causing your symptoms.

[silversleeper]

Is the exhaust leak before or after the o2sensor?
Did you check the rubber boot that comes off the afm? These are a common problem, they crack and allow unmetered air into the engine, causing your symptoms.

I recently purchased a new intake bellow, so that cant be an issue.

[silversleeper]

well, the exhaust pull off was out of the question. those nuts are rusted onto the flange for good. i think i will end up taking it to a muffler shop and get some 2.25" mild steel piping put in. i will have to wait until i order a new catback and high flow cat first though. for anyone selling a used one, let me know!

robbieosterman, i thought that only worked with the e34, where there is a little button at the bottom (full throttle position) of the gas pedal. i dont feel that click on my e30, therefore assumed that method didnt apply to my car.

btw, my car is a 1989 325i, with 65,000 miles.

[e30Matt]

well, the exhaust pull off was out of the question. those nuts are rusted onto the flange for good. i think i will end up taking it to a muffler shop and get some 2.25" mild steel piping put in. i will have to wait until i order a new catback and high flow cat first though. for anyone selling a used one, let me know!

robbieosterman, i thought that only worked with the e34, where there is a little button at the bottom (full throttle position) of the gas pedal. i dont feel that click on my e30, therefore assumed that method didnt apply to my car.

btw, my car is a 1989 325i, with 65,000 miles.

The WOT switch is there, regardless. That click you felt on the E34 was the auto trans kick-down switch.

Do like they say, and do the gas pedal trick. Then get that four number code and cross reference it with the list.

If your exhaust sounds like a WRX and you're throwing a CEL/running bad, sounds like you may be missing on a cylinder. Maybe a fouled plug or something. Let us know what that code comes out to be.

[e30Matt]

Or heat them up with a torch to loosen them. This is how most people do it.

[e30Matt]

I talked to him on AIM, had him unplug the AFM while idling. Idle rose to 750 and stayed rock solid.

I'm thinking bad AFM, blokes. Anyone local to him that can lend him one?

[silversleeper]

okay, my latest update.

i installed some new bosch platinums and the car seems to be running a bit smoother (could be mental). anywho, i found a guy selling a intake with the afm attached. he said its in working condition, so we are negotiating a price, and then i will purchase it and see how things go from there.

i played with the afm a bit. when i first started her up, she idled at about 1k, and started to slightly fluctuate. i unplugged the afm while it was running, and the idle dropped to a steady 750rpm like normal. but, with the afm unplugged (i assume this is normal) when revving, the car hesitates like a muthaf*cka. when connected again, it revs smoothly.

i drove it to work today, and it ran fine. i guess its more of an intermittent problem. i still want to get a new exhaust though. i wish those damn IE catbacks werent on backorder. anyone know of a good place to buy a high flow cat?