SteveC2375

2001 Honda Civic LX, 1.7L, auto, 219k miles.

Problems started while driving home from work one evening, suddenly the battery and engine lights came on and the car seemed to lose almost all power from the engine. Acceleration was very slow, but I was able to limp it home to my driveway.

Car starts without any problems. The check engine light flashes for the first 20 seconds after being started. With every blink of the CEL, the engine idle hiccups and you can hear a clicking noise from the relay down by the PCM behind the glove box. After the initial 20 seconds, the hiccups stop and the engine idles as normal, but the CEL stays on and the tachometer stops working.

The next problems start when you press the accelerator. At around 3000 rpm, the engine begins to surge while the accelerator is held steady. Pressing the accelerator any farther and the engine just seems to lose all power and stalls out. There is also slightly visible black smoke from the exhaust. I have also noticed that the AC compressor and the electric cooling fans have not been coming on. The most interesting part is that there are no OBD codes reading from the PCM.

I took the car to a local mechanic shop first, and the guy there scanned it, but could not get any codes. He checked all the fuses and had no idea what was wrong.

I then took it to the dealership where it was purchased, which was a complete waste of time. The guys there told me that they could not get any codes, and that my alternator was bad. They could replace it for $580, but it “might not fix the problem”. Took the car back home, and the battery measured 12.5 volts with the car off. Measured 14.5 volts with the engine running and could find nothing wrong with the alternator.

I also had the car checked out by the shop that rebuilt my transmission. Still no codes. They seem to think it is an electrical problem or possibly a bad PCM.

Any help you can give is appreciated.

gearbox

iTrader: (95)

start by replacing the clicking relay behind the glove box.

lazlong

Then reset the ECM/PCM.

helloitismee

just an idea- check all wiring in the engine bay & earths - proper contacts, and in good condition (battery greased etc), no rust.

etmotorsports

I have the same exact problem !!!! We have replaced ECU which fixed problem for .25mile.. If we unplug ELD or The Alternator 4prong plug car will run fine for a few minutes .. AS long as battery light is on car runs and we can connect thru Diagnostic port once it goes off everything dies no tach, no temp gauge no connection to code reader.. I have the dash out of car , untaped most of the harness car has been to 2 HONDA dealerships, I did find a burnt wire but that was in the combo switch Headlight I believe ,, who ever figures out the right answer 1st gets PAID !!!!! $100.00
Oh yea original ecu runs car even without immobilizer key light flashes but car runs to 3000rpm

lazlong

Check for a bad Multiplex Unit. These cars are kinda known for that. Let me know when you need my paypal. lol

etmotorsports

I thought it might be multi plex and it could be but if you shut car off unplug alternator or ELD start car it will run fine for undisclosed time (only minutes) it idles surgers during this time battery light stays on and temp gauges doesnt work but tach does .. as soon as it switches (lack of better term) car idles fine gauges reads for a few seconds tach quits workin diagnostic port quits working and car will not rev above 3000rpm

lazlong

Check the MCU:

1. Turn ignition ON (II) then turn dome light to the center position and close all doors.

2. The pic shows a "special" tool which is only a fancy jumper wire. Hook a jumper wire up to the MCU as shown:


3. Once it's connected after 5 seconds the spotlight and ceiling light will should come on for 2 seconds then go out and come back on for 0.2 seconds to show it's in Mode 1.

4. If it doesn't come on then check continuity between terminal 4 (black) of connector J (ref- 21 in the pic) and body ground.



Is there continuity?

YES- replace MCU

NO- repair open in wire. if wire is good, repair G301. (I'll tell ya G301 if you need)

etmotorsports

wondering if I can start car during this test .. if it comes back as MCU is ok because as I said when we first start car it seems to run ok for a few minutes.

D.J.

lazlong

It said to "turn to ON(II)" it didn't say anything about starting the car.

etmotorsports

I understand if the test comes back ok I think a further test maybe required in that the car runs fine for a few minutes, then it goes haywire .

D.J.

ps. I do appreciate the help . 1st car in 15 years getting the best of me

and I have done some crazy things ie. turbo insight , turbo tiburon , turbo focus, 3000gt automatic turbo , I own a 410hp stock motored 89 colt turbo (well stock except head gasket and ARP to handle the 27psi from 60

lazlong

The lights coming on for 2 seconds, then off, then on for 0.2 seconds indicates Mode 1. If in Mode 1, the lights will then blink your DTCs. If no DTCs, go to Mode 2.

DTCs:

Mode2:

Sleep and Wake-up:


Tell me if you need the input test. Sorry about the fuzzy pics, phone cam.

etmotorsports

well put in a new Multiplex (test were all over the place) anyway back to square one ,, Car wont rev above 3500 rpm (even with alt unpluged) Immobilizer flashes all the time , can not connect obdII port ,, the ecu has already been replaced ,, come on Peeps Ideas !!!!!!

htulrich

Same problem here except mine started when the alternator bolt broke. I haven't done any multiplex checking yet. But it doesn't sound like that fixed it anyway.

flyfast727

Have the same prob with my 2005 Civic HX. Alt bolt missing, belt started squeeling, replaced bolt/belt. Bat light comes on goes into limp mode Etc. Etc. Replaced Alt no help. Surely you guys have fixed this by now. Can the people to this thread respond and tell what was the fix?

gearbox

iTrader: (95)

usually losing that bolt causes grounding issues that can damage the ecu. i've seen it many times before on these cars. plug in an obdII scan tool and see if its able to connect (even if there are no codes). if it cannot, the ecu is bad.

anibis

What bolt is the problem? The long one? I'd like to replace it with a higher quality bolt if it's a common problem.

I've replaced the alternator in my '05 twice (thanks to DURAcrap) and all the bolts seemed robust....

Fly I cannot find the thread (not sure if it was on this site or another) but another user had the same issue with the alternator bolt breaking. After the alt was replaced they had a flashing CEL and the car was in limp mode. They never posted a solution but I do remember them saying that no code could be pulled from the ECU which would mean the ECU is bad.

See if you can pull a code, if not, buy a used ECU on ebay.

Make sure you get one that matches your transmission and if you have side air bags.

flyfast727

Its the long bolt that fell out of mine and the alt came came loose. Belt squeeling etc..

I ordered a new ECU from Majestic Honda, waiting for it to come in. After it goes into limp mode, the scanner just says Link Error.

gearbox

iTrader: (95)

yeah the bolt looks fine, but can back out on its own from vibrations. just remember you have to get the car to the dealer for them to swap ecu and reprogram your key otherwise the car wont start at all if you just swap the ecus.

ababcock

I would really love to have an update on this thread. My problem is exactly the same after alternator tensioner bolt sheared off. I'm looking for an ECU/PCM but would like to know if that fixed this problem.

Thanks

thardie

I had this problem too (clicking main relay, flickering CEL light), and found I'd forgotten to bolt the one of the grounds on the engine. In my case, it was the ground just to the left of where the thermostat is (not to be confused with the ground that goes from the thermostat to next to the hood latch). This ground has too wires on it, and goes into a wire harness that heads back towards the firewall.

I also had intermittent cabin lights when opening any door. This was a rusted ground which is on the driver's side under the window washer reservoir right behind the driver's side impact sensor (Careful!)

Radianceautospa

Bringing back this thread from the dead. Come on guys has anyone fixed this it seems common on our gen but no solutions yet.

iteadjoseph

Had the same problem on my 03 civic. A new ECU fixed it for me.

Lenox273

Hello,
I have been chasing the same exact problem for a friend. Charge indicator on all the time, engine idle surging and momentarily dropping out the same time that the relay behind the glove box clicks. This happens every 20-30 seconds and after a few minutes the relay stops clicking, check engine light comes on, tachometer stops working idle is elevated and steady and severe lack of power. If you are monitoring it with a scanner it will lose communication when the check engine light illuminates. I found an answer for a portion of the problem. The ground at the top of the cylinder head above the upper radiator hose connection was faulty. I checked continuity from this connection to the neg cable and had .3 ohms resistance. Looked ok to me. I decided to try to manipulate this ground while the engine was running and problem was occurring. As I tightened the ground more it made no difference. Then I tried to loosen the bolt to move the ground lugs to the position they were in before. Accidentily loosened it too much and stalled the engine. I retightened the connection and the car has been running fine for quite a while tonight. The charge indicator is still on but the alternator is charging. Will get into that next if he wants to chase it. Will replace the ends tomorrow and drive it more. If I can I am going to post a pic of the ground lugs. Hope this helps someone out there.
Lee

gearbox

iTrader: (95)

i replaced the factory grounds a while back and also redid that ecu ground you are pointing to with a ring terminal. as a temp fix, you can get sand paper and clean both the ground strap and the block surface of corrosion.

Wirenut

Same problem for my 2001 civic. mine started after an ac compressor swap. thought it was alternator but seems to be charging ok. Anyone have luck with this one yet?

ezone

You pulled the alternator loose or off, right? Make sure your alternator mounting bolts got tightened back up. If they are loose then tighten them and pray you didn't kill the PCM.

Wirenut

yep removed alternator to get access.. will check the bolts.. also going to check out the ground strap mentioned earlier.. hoping like hell its not the ecu/pcm !!!!!!!!!

ezone

Here's a copy of Hondas bulletin on loose alternator bolts

http://www.underhoodservice.com/issu...ontentid=88560


HTH

Wirenut

thanks ezone.. mine will start. it runs poorly and gauges, fan, ect.. work for about 10-20 seconds at the same time i can hear a "click" from the glove box area. with each click the engine falls out then rebounds. after about ten clicks the tach, fan, ac compressor all stop working. then check enigne light comes on and engine smooths out, but with very limited power. try reading code, but just get flashing 8888 "link error"