1990 Maxima problems..

[patterned]

Hey guys.. New here. Glad to see there is a good forum for Maximas.. I chose the right car, I hope!Picked up a 1990 Maxima recently, and I need some advice on fixing this darn thing.

Here's how it has progressed:Car would idle rough, drove with a misstep.I replaced a fuel injector and the problem cleared up, somewhat. I bent the EGR gasket.. somehow forgot to tighten it up all the way and ran the car for a little bit before realizing my mistake. After tightening it ran somewhat better, but I still could feel some vibrations every now and then. I've got a new gasket for it, just haven't put it on.A a couple weeks after replacing the fuel injector, the car started idling perfectly (didn't search at all) and it ran/shifted just great.

Of course, the problem just came back with a vengeance.She is riding rougher and weaker then ever (I feel like I'm on 4 cylinders)... at idle and in drive my RPM swing wild (between 800 and 1500 in idle..). While driving, let's say 45 mph, I can feel the car stuttering/jerking with no real pattern (like it's dumping to much gas.. then too little.. then just right.. etc, etc)Sometimes, after putting it in park, the RPM will rocket to about 2200 and piddle around up there.. if I wait long enough sometimes it drops back to 1500.. sometimes not.

I pulled the distributor cap off today and there are two separate cracks directly across two of the lines. There is no major carbon build up inside the cap, but on some of the contacts there is a little rust(?) [which I scraped off in hope of it helping]. Is it possible that these cracks are at the heart of the problem?

I plan on pulling the EGR valve and IAC valve and cleaning those, and replacing a bunch of vac hoses. Anyone have any tips on cleaning them? I've heard of dumping the EGR into a bucket of carb cleaner and letting it work itself out. Is this standard procedure?Anything else you could point out for me that I'm not looking at?Links, etc., are well appreciated!

Also:My MAF sensor.. I'm confused with this guy. I was tinkering around with the wire coming from the harness, and the engine started to stutter. So I turned the car off, pulled the connector and pushed the wire leads down so it would grab the wires better. After doing this, I turned the car back on, and messing with the wires caused nothing. Success. Only problem is, someone told me to pull the MAF connector with the car running to see if it is the problem (I was told the ECM will be forced to defaults). When I pull the connector the engine immediately dies. Is this indicative of anything particular?

Thanks for the help, guys!

EDIT: While I'm here, I should also point out something extremely weird (to me). For a while, my car would not start without me first pulling the fuel pump fuse out.. turning the ignition, and letting the car idle for a second.. and plugging it back in. It only does this to me once in a while now.. but can someone please explain what is going on here? Vapor lock?

[MinisterofDOOM]

The distributor cap cracks are almost assuredly your problem. I had a very similar problem a couple years ago and my distributor cap ended up being cracked the same way. I replaced the cap and the car ran like silk again.

[patterned]

Thanks Minister! Good news, cause that's only gonna run me like 20$. Phew

Is there any chance you can answer my other questions?The fuel pump fuse question particularly.. I can't seem to come to any logical answer to why it would do that.And unplugging the MAF kills the engine.. What does that indicate?

[Blazingwolf]

Um just saw a car today that was 1993 and the wiring harness to the injectors was bad and it had a rough everything.. check that and see if u find anything

um unplugging ur MAF i don't believe would kill the car but it should def make it run like poop and though a dtc or check engine light

[patterned]

Well I ordered a new distributor cap and a rotor from RockAuto.com

They sent me the wrong cap but the right rotor. Excellent customer service, by the way. I called them on Saturday, explained what happened, and they shipped one right out to me on Monday morning.

I put the new rotor on, and my car is running 90% better (I guess closer contacts/stronger spark).Hopefully the other 10% is the cap, and I will have that installed as soon as it comes in the mail.

I'll report back here when I figure it out!

Blazingwolf:My car dies immediately after unplugging the MAF. If it's supposed to run like poop after unplugging it, then I see why it would die in my situation (spark cross contamination.. or whatever you want to call it).I'm guessing thats why I was having to pull the fuel pump fuse in order to start the car (too much gas in the lines.. had to pull the fuse and crank for a minute to start, then put fuse back in).

Now other problems show.. seems like after starting the car, the starter stays engaged and I get a good 3-5 seconds of loud clicking, until it disengages. I don't know much about starters.. so maybe I'm just making stuff up..?Does that make sense to anyone?Any cure for the problem, besides a new starter (if it is the starter)?

[canucklehead]

usually when the starter won't disengage, it's telling you the end is near...at least that's been my experience with other stuff.

I'd also check plugs and plug wires (you already did fuel filter, correct?). just a good 'ol basic tune up. AND air filter.

don't know your fuse/fuel pump issue, that's just wierd and read my post about the filler neck on these. I'll be putting it up soon.

[patterned]

Thanks canuckle.I figured my starter was going out. It's a fairly new starter on this car.. Figures.

When this whole problem started, I replaced the plug wires, spark plugs, and fuel filter.

Here's the update:I got the distributor cap in. Installed it (it's not an OEM.. it's a Bosch, if that matters), and the damn car starts running worse then before!Grab the toolbox, run to the auto store.. get some new vacuum hoses and some carb cleaner.Proceed to clean the throttle body, IAC, and replace a couple of hoses (I don't know much about what hoses do what.. so I replaced a couple that looked bad). Also sprayed the MAF sensor with the carb cleaner (bad idea?).Then I pulled the PCV hose, and stuck a can of Seafoam on the valve. Ran about 2/3 a bottle of it through the engine. I felt like some WWF wrestler was gonna come out from all the smoke...Let it sit for 10 minutes and fire her back up.She runs good... except for a hick up every now and then (very random.. no pattern, just hick ups like it's missing a spark or something).

I take her for a 15 minute ride out to a waterfall and hang out for a minute.I get back in the car after a good 30 minutes and start it up. It starts searching for idle between 1 and 1.5 RPM again.And I'm stuck again. I can't figure it out. I can start it one hour, it will idle perfect (800 RPM), then start it an hour later, and it will search for idle for the longest time. Sometimes it will correct and find idle, other times no matter what, it won't find it. When I put it in park, sometimes it will jet all the way up to 2 RPM and sit until very very slowly lowering idle down to 1.5. Sometimes I put it in park and it drops idle right to 800-1000 RPM.It's like a woman on her period. I don't understand what to do.

I would like to avoid going to the shop for this one, if at all possible, so I can learn more about my dear maxima's engine.

Can anyone give me advice as to where to look/what to replace??I'd love some feedback!

Is there any way my fuel pump could be causing this??

More info: My exhaust smells like the car is running rich, or not burning all the fuel. I definitely feel like I'm running on all cylinders again, though..

Thanks!