Since I was only waiting on a clutch hard line to finish this project, I decided today to bastardize a Honda line I had laying around. So I did that, bled the clutch, and I took it for a test drive for the first time today. When I (attempt to, at least) accelerate, it seems to be losing power intermittently. It'll rev to about 2k, lose power, catch, bog, buck, nearly die, sputter, then I'll rev it some (or try to), and it'll accelerate normally for a second or two, sputter, lose power, catch, bog, etc. It died on me two times as well.

Now, in the driveway it idles just fine, and revs perfectly smooth all the way up to redline. Doesn't have a miss or putter or anything at idle or when revving in the driveway. It only does this when I'm trying to drive the thing. All injectors check out perfect (each of them is at 11.2 ohms). I swapped MAFs with one of my other cars and ruled that out.

Plugs are new, fuel filter is new, fuel pump and gas tank are new, etc.

Oddly, it kind of feels like how a car feels when it's running out of gas or something

I read through some of the older JDM swap threads I could find, and everybody mentioned changing the coolant temp sensor and I made sure to do that already. I saw other mentions of the IACV but I don't think that's the issue here because the idle doesn't hunt, surge, and isn't high. It's rock solid at about 700 rpm.

Thoughts?

 

Looks like you covered it. Does it do this when it's cold and when it's warm? You could try swapping out your fuel pressure regulators.

 

Good question. Not sure if it does it when cold as i had it idling in the driveway for probably 10-15 minutes before I drove it. I drove it again a little later but the engine was still pretty darn warm and the temp gauge got up to operating temp immediately.

A really strange thing was occuring that I forgot to mention - when the engine was doing its goofyness when I was trying to drive it, I noticed that the gas gauge needle would fall all the way to the bottom, like, allllllllllll the way past empty (i.e., even below where the needle would be even if the tank were all the way empty). Then when I would get it back to the driveway and shut it off, and then start it up again the needle would then slowly move back up to the proper spot. WTF?

 

seems like ur fuel level sending unit going bad...u should take the fuel pump out and inspect it plus check the fuel pressure if it is according to the specs...

 

Sounds to me like a +1 .......... or bad wiring/connections to the new tank/pump etc assembly.

Slap a meter on the fuel rails and it should be easy enough to see

 

yeah, I'm thinking bad connection at the tank

 

I originally put a new pump and tank in because the old pump wouldn't even come on, and was completely coated in hard mud type stuff as well as sticky black goo. I replaced the tank because it was also coated in the same stuff and just full of rust. I spent about an hour scraping off rust/grime/muddy stuff from all over the sending unit/float deal as well as the fuel pump mounting hanger before installing the new one.

The pump I bought is a Carter semi-universal one that came with a couple of butt-connectors to wire it up, but I'm positive they're on there solidly. I did notice when it's idling it makes a sort of "churning" noise from the pump area but just chalked it up to it being an aftermarket one.

I've never had a fuel sending unit go bad. Would a bad fuel sending unit necessarily cause fuel/driveability issues aside from a flukey gas gauge though?

Anyway, I'm off tomorrow so I guess I'll just rule out an issue with the whole fuel pump "assembly" by swapping in one from one of my other and seeing how it goes.

 

i doubt it. i think they were suggesting that the wiring to the whole pump/sender unit as a whole had an issue, like a shared ground or something? not familiar with the exact wiring layout of that part of the car but perhaps the 2 systems have a shared wire or 2.

 

did u test the ignition coils? sounds like thats the culprit

 

Probably fuel related like others have suggested- but have you Ohmed out the CTS for ****s and giggles? We have tons of returns for bad new and reman CTS's out of the box- so... might as well rule it out.

 

What is the CTS? I don't believe I've seen that acronym before

*edit* oh, duh, is it the coolant temp sensor? It's brand new, but I guess I could check it anyway.

 

Coolant Temp Sending unit. It tells the ECU when the engine is warm or cold, effecting the amount of fuel supplied to the injectors.

 

This may help as well. http://forums.maxima.org/3rd-generat...nsor-ohms.html

 

James, is there another thread that covers why you swapped your VE out for a JDM. I'm new to the VE world, but have gained a mountain of knowledge in the past couple weeks. I'm always looking for more information on these beasts and track records from what I can expect from mine.

 

you can start a thread or do some searching on VE engines on this site. Lots of info.


James, you might want to swap in a full set of coils from your other VE to at least try to rule that out.

Did you check the ECU for codes? The only code my car has ever thrown was when the coolant temp sensor was bad.

good luck -- I know how frustrating these things can be

 

Probably mentioned but perhaps you are losing power to the fuel pump?

 

Well, I bought the car for $200 with a blown automatic transmission. I planned to do a 5 speed swap in it just to get it going, but once I got into the engine a little bit I noticed how badly taken care of it was, and since I'd had a JDM VE in the garage for a couple years I just decided to put it in (along with replacing/rebuilding everything else on the car - this $200 car has turned into an over $3k project ).

Back to my issue - well, it turned out to be the new fuel pump. The pump was/is brand new

I pulled the pump out of one of the other VE's, and swapped it in and now the car has no bucking/dying/etc. symptoms whatsoever on acceleration. I still haven't REALLY driven it out on the open road as it's not registered/inspected yet but

I checked the new pump for maybe a bad connection (it's the kind you have to butt-connect into the factory power and ground) but couldn't find anything loose/wrong at all. It tests out fine, works just fine at idle and revving in the driveway, but acted like it was running out of gas when I tried to accelerate in gear. So who knows. I think I'm just going to buy another complete OEM pump assembly and skip the universal aftermarket type stuff.

 

lol i know EXACTLY how you feel. I got my '85 z31 with a dead engine. But the front struts were also dead so i was like eh, might as well do them too. But if i do the struts i might as well put lowering springs on it while i'm at it. And if i'm gonna do that i might as well put swaybars on. And if i'm changing all that i might as well put polyurethane bushings on it. And if I do all that I'm gonna need an alignment. And if I get an alignment i might as well get new tires to further improve my handling. And if i get new tires i might as well get bigger and wider wheels and do a 5-lug swap. And if I do a 5-lug swap i might as well use the vented 87-89 rear rotors. And if i buy new rear rotors i might as well buy new front rotors too. And if I'm working on the brakes i might as well get Hawk pads and SS brake lines.......... yea. see what i mean?

 

Ha ha.. ain't that the truth. Where do you draw the line???

 

it's hard to say cuz it needs a new driveshaft (siezed u-joint) and new half-shafts... so i'm debating putting an LSD also

 

Hmm. I would love to, as soon as i get enough posts to get past my Newbie state. I guess I haven't rambled on enough in the newbie thread to earn the right to post new threads.

 

I got lucky on the LSD thing, the SE came with it. But I did install a helical style lsd in my 03 altima. Not a fun job by any means, but hey, it's water under the bridge now. Sure helps with winter driving, well worth the $600 for the part and fluids.

 

i know.. well, the 92-94SE anyways. 89-91SE had VG and no LSD. but my 5spd Civic has an open-diff and i keep one-tire-fire'ing in the rain.... the VLSD on the VE tranny was stealthy at times but it sure kept me out of trouble on my 3rd gen.. too bad the maxima tranny won't work on the civic haha. but that's the one thing about civics, parts are very available. front/rear poly engine mount inserts from EnergySuspension were $32 shipped. I will say that the VLSD swap was worth it as long as you don't have the problems i did - getting hubs with good wheelbearings, and the stupid rusted-on shift rod yoke preventing me from changing the striking rod seal. frankly i doubt that tranny has much fluid left in it since the car has sat for 2 months.

 

That's the exact same thing I did with my '89 Civic last winter. It developed an oil leak and that turned into a complete engine rebuild, MPFI conversion, rebuilt/new Si transmission, all new suspension, new paint, new door moldings, new carpet even. The thing is basically a brand new car but I ended up spending close to $4k total

And I spoke too soon on my fuel pump issue. I got it registered and insured today (still no inspection though, but insurance and registration is good enough for me to justify driving it around ), and took it out for some extended driving. The longer I drove it began hesitating/stumbling but not near as bad as the previous pump did (just driving it around the block the other day it was nearly undriveable and I was scared it would strand me).

Now, it's not near as bad as it was, but it's still noticeably stumbly/hesitant when accelerating and definitely lacking some power. So now I guess my issue is hesitation/stumbling when the engine is warmed up. I think I saw a flow-chart in the FSM for something like "hesitation when engine hot" or something, hopefully I can run through that on my next day off.

And I added up my total so far - $3,371.15, and I still have to do paint and body!

 

:O That's a good amount of money to put into a $2K car.
I've got $800 into my 92 so far, and am debating spending $300 on replacing the timing chains or $650 plus fluid to swap a JDM engine into her. Then I've still got a tranny leak to fix, a leaking windshield to fix, and alignment.

 

Bump:

Well, it's still doing it. I'm now on my 3rd fuel pump assembly. It killed the pump I swapped in from one of my other VE's. I think the filler tube had sand/crap in it and it allowed sand/crap/dirt get in the new tank already and ruined the pump. The strainer on the pump was just full of sand/dirt, and the fuel filter was clogged. I poured this out of the "back" end of the fuel filter (i.e., opposite side of the engine, so none of this went through the filter to the engine):



So, I again dropped the (new) tank, cleaned all the crap out of it, dropped the filler neck and cleaned it all out, and put in a junkyard fuel pump assembly and new fuel filter. Now that I've driven it a half dozen times I can most definitely say that when it reaches operating temp is when it starts to bog/hesitate/stumble/lose power etc. It's consistent. Before it warms up all the way the sucker is powerful as can be.

I'm really getting kind of at my wit's end with this POS :angry:

 

Check the Fuel pump relay in the trunk next to the left stop light.
Mine used to do something like that and I changed the relay.

 

did you put in a NEW coolant temp sensor or just swap the one over from the old engine?

 

No, it's brand new. Would the coolant temp sensor cause hesitation/stumbling/loss of power? I thought it just made the fans go crazy.

Maybe I'll put in a different one. At this point, it can't hurt. On that theme, I noticed just today that the car runs just a little bit on the hot side. The temp gauge sits just a little bit higher (though noticeable) at operating temp than my other two VEs. Just barely though, maybe a couple millimeters.

 

Couldn't that be because you put in a new gauge? If the gauge is brand new, could it be that it's reading a more accurate temp of your coolant level than your other vehicles?

 

Well the gauge itself is the OEM gauge. Or by gauge are you referring to the coolant temp sensor?

 

Try checking your ignition timing. Symptoms are very similar to what I've seen before - engine runs fine no load, hardly runs at all under load. Do you have a distributor on the 3rd gen? Is it a toothed design? If so, make sure that the rotor is phased properly to the crank. One tooth off will make a big difference.

 

But why would it only not run fine when it's at operating temp? Like I said, it pulls like a bat out of hell before engine warms up.

This is a VE so it doesn't have a distributor

 

cam pos sensor... it's been said that the cars deliberately run more advanced timing when cold, so maybe your timing is normal when cold but retarded when warm?

 

I think I figured it out, and it is/was timing related. The timing marks on my UDP appear to be WAY off. When the timing is set at 15 deg. per the UDP, the thing runs like crap when it warms up but runs fine before before hand (like you said Caped). I screwed with this for a few hours this morning repeating the problem for consistency sake.

Eventually, I got fed up and just started turning the cam position sensor a little bit, driving it around the block, coming back, turning it a bit more, etc. Obviously, this took forever. I found a spot that "feels" right, but with the cam position sensor in this spot, the timing marks on the UDP aren't even visible, not a single one. But it "feels" right driving and sure pulls hard. I drove it around for about 30 miles and it never started bogging/hesitating/etc.

Now my problem is that I have a JWT ECU I want to run, but I don't want to put it in unless I know the timing is exact. I suppose I could let the dealer set it with all their gadgetry but ugh I really don't want to deal with them

 

maybe your timing chain was previously r&r'd and isn't lined up right if that's the case... that or the pulley was just made wrong. do you have a stock pulley to test with?

 

Hmm, I'm nearly certain the VTC's are new (actually new, not rebuilt), and I can tell something in there has been worked on but I have no clue whether it was just VTC work or any additional work

Although, if the chain isn't lined up right, wouldn't that only mean that when the pulley "says" it's at a certain degree, that its not actually at that degree? Aside from a tooth misalignment, I guess it's all the same operationally.

I think I do have a stock pulley somewhere

 

if the valve timing is off it could just respond differently to different cam timing

but the stock pulley is your best bet to try first.

 

If it seems to be timing related, have you ruled out the knock sensor? It could be pulling timing like crazy when the car warms up but working fine when then engine is cold. I had a similar problem when the car warmed up it would bog and have basically 0 power... I didnt have any stalling or anything though. Maybe try disconnecting it and throwing in a resistor to see if anything changes?

 

yeah, sorry for taking so long to respond.... I'm referring to the coolant temp sensor