Intermittent slow start/long crank

I have a bit of a head scratcher on my hands here with my 2008 Chevrolet HHR 2.4 L.

I’ll keep it as brief as possible, but I want to provide as many details as I can to help diagnose/fix the issue.


After the car is sitting for ~3 or more hours, it takes longer from cranking to starting. If it’s sitting less than that amount of time it seems to start fine.

The problem initially started last Fall. However, at that point the issue didn’t require as long inbetween episodes. I then discovered a rusted/leaking fuel line near the L back wheel. The bad section was replaced with rubber hosing (rated for pressure/fuel), and the problem resolved. It returned about a month ago with the same signs. I assumed that either my patch job was failing or further rusting/leaking was developing. I replaced both fuel lines, but the problem remained.

The ambient temperature impacts how long of a delay there is as well as whether and how long it idles roughly (colder = more delayed, long rough idle; warm = shorter delay, no rough idle). When it occurs, the rough idle lasts for anywhere from 3-20 seconds (longer when colder) and then smooths out. In all of the time the issue has been present, the car has only died once during the rough idle.

After getting the car started through the delay, I can immediately turn off the car and restart it with no delay or problems (doesn’t matter if car was running for 1 second or 1 hour, it will immediately start once turned off and back on).

Once the car is running, it seems to have no issues.

The check engine light came on at the end of last week and gave a P0442 code (small evap leak). I couldn’t find an obvious cause, so last weekend I swapped out the EVAP vent and purge valves/solenoids to be safe (yes, it was probably unnecessary/overkill, but they’re cheap/easy to replace; I was tired of messing around and figured it was worth trying before dropping the tank/replacing the fuel pump). I cleared the code, and it hasn’t returned so far, so we’ll see how that goes.

There is no evidence of a fuel leak along the fuel lines from what I can tell (based on visual inspection, no gas smell, and no findings when using a combustible gas detector).

Fuel pressure (measured at the rail) is within specifications as listed in the Hayne’s repair manual.

I swapped out the fuel pump assembly yesterday since HHRs are known to have fuel pump problems, and some HHR people had suggested it as a possible cause of the problem. Unfortunately it didn’t solve the problem.

Something that I recently noticed (a few days now, may have started longer ago) is a short burst of sound when I turn off the engine. It almost sounds like a small electrical motor activating. It seems to be coming from the rear half (driver’s side) of the engine on the side nearest the windshield. I couldn’t find the exact source and have no idea if it’s even relevant to the issue.

Here’s a link to a video with the sound: https://youtu.be/5DNCetYMAuU
It’s the small buzz/burst of sound shortly after the engine stops.

Also, here’s a link to a video of the delayed/slow start. It also shows the fuel pressure during one of the episodes. Sorry about the windshield wiper getting in the way of the video (didn’t realize it was on until it was too late, and, since the problem takes several hours to reoccur, I couldn’t just restart the car to re-film it). https://youtu.be/YgDfilURvsU

I did check the air filter housing, air filter, wooly worm, and spark plugs today. Everything seems fine except one of my coils (cylinder #1-furthest on the passenger side) had a very small smudge of brown gunk on the outside rubber/on the wall of the spark plug well. That spark plug appeared normal with no evidence of anything on the electrodes, threads, or ceramic insulator. The spark plug well itself also appeared otherwise normal except for the small smudge on the one side of the wall. All four spark plugs seemed normal with normal gapping and electrode appearance.

The battery voltage measures fine with my multimeter (both with the car off as well as running with the alternator).

Any thoughts?

Let me know if there are followup questions.

Thanks!!

It does sound like your starter is getting bad. First, check if all connections from the battery to the starter motor are solid and has 12V.

Hey COROLLAGUY1, thanks for the quick response!

I’ll check the connections later today, but I have a couple of questions.

Why would a bad starter cause that sound when turning off the engine?

Also, why would a bad starter only intermittently cause an issue (after sitting for 3+ hours but not if sitting shorter than that)?

Thanks again!

Drive pinion on the starter is getting stucked and not retract completely from the flywheel when you shut down the engine.This is due to burnt or worned solonoid copper contacts.You can replace those yourself (depending on starter) or buy a new unit.

Your second question: Engine heat will unstick the starter pinion but will stick on a cold engine.

The original unit for your vehicule is made by Denso . You can repair it yourself with a $10 kit on ebay. The kit comes with 2 copper contacts and a plunger. It takes around 20 minute of work to replace.

Does this mean the starter motor is running whenever you want it to, but sometimes it cranks for a longer time than usual before the engine starts?

That was my understanding. That would not be a problem with the starter motor.

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That’s correct. The car has never failed to crank when I turn the key. It just cranks for longer before starting if it sits for a few hours (temperature dependent - longer crank when cold outside, less so when warm).

I can immediately shut the car off once it has started, and it will start immediately thereafter (unless it sits for another few hours).

Try the key dance: from Off to Run, wait for the fuel pump to run a couple seconds (you may hear it), then Off. Try it a couple more times and then turn the key all the way to Start. Any diff?

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Nope, no difference. With regard to fuel pump/fuel pressure, I pressure tested the fuel system (at the fuel rail), and it was within specification (per the Hayne’s repair manual)

After letting the car sit for ~6 hours, I hooked up the tester. The gauge read 0 PSI. I turned the key to the run position without cranking the starter. I heard the fuel pump engage, and the gauge immediately jumped to around 58 PSI. I then started the engine and let it run for a couple of minutes. The pressure stayed consistently around 58 PSI. I then turned off the engine and monitored the pressure over time:
0 minutes - 56 PSI
5 minutes - 52 PSI
10 minutes - 51 PSI
20 minutes - 47 PSI
30 minutes - 39 PSI
60 minutes - 34 PSI

According to the Haynes manual, it shouldn’t drop more than 8 PSI in 5 minutes

I then left the gauge hooked up overnight. It read ~17 PSI when I went out there in the morning.

Upon starting the car, it did the delayed start (took ~2-3 seconds from crank to start). The pressure jumped right away to ~60 PSI as soon as the key was turned. Once it started, the pressure rapidly bounced from ~50 to ~60 PSI for around 15 seconds before abruptly stabilizing at ~57 PSI.

I haven’t had a chance to investigate the start yet (plan on doing it tomorrow). However, I did listen underneath the car for the sound after the engine stops, and it does sound more pronounced.

Here’s a link to a video recorded under the car (right near the starter) that has the sound more pronounced/easily discerned: https://youtu.be/39jhmVM1cxM

I’m planning on lifting the car up tomorrow so I can be underneath it to try and really pinpoint the source of the sound and look at the starter further.

Thanks again!

Your thoughtful approach is impressive! It seems that lack of fuel or fuel pressure is not the problem after all. Possibly it’s the opposite: leaking injector(s) making the mixture way too rich in one or more cylinders. To clear that out more quickly, try holding the gas pedal at least partway down while cranking.

I have to give you a thumbs up on all you’ve done so far. Pretty much spot on. I’m surprised you’re still plagued by this frustrating problem. I would have guessed it was a fuel pressure problem, but you’ve pretty much ruled that out. So, hmmm … well, here’s some other ideas anyway

  • starter motor isn’t turning the engine fast enough; i.e. isn’t as robust as it should be. Will show up more when the ambient temp is cold or the engine is cold. Battery connections corroded, battery bad, starter bad. What does the battery voltage measure at the starter during cranking? Both terminals, to starter case.

  • the engine computer isn’t injecting enough gas on cold starts. engine coolant temp sensor, ambient air temp sensor, ecm or fuel injector problem

  • engine compression is too low, measure it

  • If it isn’t the problem CorollaGuy mentions above, no idea what’s causing the noise when you turn off the engine. It’s probably some actuator going into its park position. Could be a vacuum leak too. Check the brake booster holds vacuum, and do a fuel trim measurement

It takes 20 minute to remove a starter on this car. You can bench test it if you have a set of booster cables.

Removal and installation video for a Chevy HHR

I removed, inspected, and bench tested the starter. It seems to be working perfectly and has good, clean connections.


I did some voltage testing of my battery yesterday and today out of curiosity/to be thorough.

I bought the battery new last fall (2017).

I tested it last night when going after the starter, and it read 12.36 V, went down to 10.9 V when cranking, then up to 14.8 V with the engine running.

When I hooked up my multimeter this morning, the battery read 12.35 V, went down to 10.9 V when cranking, then up to 14.9 V with the engine running.

However, when I checked it this afternoon. It read 12.6 V, went down to 11.9 V when cranking, then up to 14.9 V with the engine running. It still did the hard start, so I’m not sure I can blame it on the battery.

I then checked it again when leaving work, and it was still at 12.6 V.

It seems the alternator is fine since the voltage goes up when the car is running. I’m not thrilled about seeing the voltage at less than 12.4 V, though. Since it still had the starting issue when the battery was at 12.6 V, I’m not sure I can blame the issue on the battery though. I’m thinking of going to the place I bought it and having them test it more thoroughly or replace it just to be safe (still under warranty).


Someone I was speaking with suggested that the EVAP leak (P0442 - if still present - can’t confirm since the check engine light hasn’t returned) could be leading to the hard start. Any possible link between the two (vacuum related, perhaps)?

Thanks again for all of the help, everyone! Fortunately the car has never failed to start (yet) and runs well, so I’m not in dire straits. At some point I may have to bite the bullet and see a mechanic or simply wait until the problem becomes more pronounced/clear/easier to identify and then diagnose and fix it (although the risk of being stranded is definitely on my mind if it ever decides not to start at all).

Thanks for the suggestions! It’s nice to have some options to pursue (since I’m running out of ideas).

I’ll look into these and let you know if I find anything.

Some of the prior tests seemed a little low, but still within acceptable limits. Those above are 100% acceptable voltages, and since the problem happened on that crank, it must not be a power supply problem to the starter’s B terminal. To be complete You should do the same test for the starter’s S terminal. Those were made at directly at the starter between the starter B terminal and and starter case right?

Have you tried spraying some ether (starting fluid) into the air intake to see if that makes it cold-start better? If it helped, you’d have a clue the problem is fuel related at least. Best of luck.

I can try to check the S terminal, but that one is tricky on the HHR since it’s a plug-in/wiring harness not a bolt/post like a lot of starters. Any tricks on testing a wiring harness?

I tried that once, and it didn’t seem to make a difference (indicating a fuel delivery issue being unlikely). I’ll give it another shot to see.

If the starter fluid doesn’t help, that would rule this out, right? Is there any other way to test this?

Any thoughts on this?


One of the toughest issues I’m having with this problem is that it takes several hours for it to reoccur. That makes reproducing and directly testing different things require a lot of time and sitting around. It also means I get one opportunity every few hours to try various direct diagnostics/fixes. Obviously there are things I can check in between, but it would be nice to be able to replicate it more easily/quickly for diagnostic purposes.

I’m seconding George_San_Jose1 here: The ECT is referenced by the cars ECM at startup to pick values from an internally stored table that determines pulse-width-modulation settings for the fuel pump. Because the sensor reading is in range of what the ECM expects, it would not trigger a DTC code. But if, for instance, the coolant was at 60F and the ECT indicated 80F, the fuel pump would be set to deliver about half as much volume. The fuel injectors are using a combination of the ECT and MAF/MAP sensor data to pick a value from a different table to determine how to run the injectors. That is why you see huge fluctuations on your fuel pressure during the initial run period. The injectors are trying to flow more fuel than the fuel pump is trying to provide. After several seconds of cranking and a few minutes of stumbling, the actual temperature of the engine comes within range of what the ECT is reporting, the injector duty cycle decreases, and the volume of output from the fuel pump is matched to the volume of output from the fuel injectors. Spraying starting fluid would not affect engine temperature, nor would it change the PWM signal to the fuel injectors.

(I’m going to rule out the fuel pressure sensor because you did replace the fuel pump assembly, and it’s part of that. Also, I think the fuel pressure sensor data grossly controls PWM settings across a broad range.)

The ECT is a $10 part. You can check it with a digital multimeter. The values should be in your manual. Or, just swap it and see.

It may also be the case that the MAF/MAP sensor is involved in choosing fuel pump PWM settings for your vehicle, or they could be overdriving the injectors. This is where mode 6 diagnostics for ODBII can save a lot of time, money, and frustration. You can get scan tools capable of displaying live sensor data for $60 these days. I bought one and it has saved me a small fortune on educated guesses.

It depends on the situation. Sometimes I cut the wire and solder in a test pigtail. Other times I use a straight pin to poke through the insulation. On some connectors it is possible to back-probe, may need to push some insulation away for access.

You are correct. As far as testing, on my old VW Rabbit, if I was suspicious the injectors weren’t doing their thing, I’d pull all injectors and put each in a jar and measure how much they were injecting , using a stop-watch to obtain a flow rate.

If there are any engine related diagnostic codes common sense says they should be addressed first, before assuming something less well defined is the problem. You can have engine codes stored in memory without a check engine light. The evap system is like a balloon; it can leak anywhere. It is hard to predict what the effect of a leak might be on engine performance, until you know where it is leaking. Sometimes a leak causes fuel to be drawn into the engine when it shouldn’t be; other times a leak may be related to a vacuum forming, preventing fuel from being delivered from the tank to the engine.

Have you done a compression test? B/c low compression could cause this. Also an o’scope analysis of the ignition system might show something. I expect you already know that hiring a shop with a Chevy scan tool to offer an opinion what’s wrong might get you to the result faster. Those make specific scan tools make all sorts of testing methods available at the click of a button that a diy’er can’t do themselves. You could ask them what’s wrong, then you could fix it yourself. You seem to be pretty diy’er skilled, so if you keep poking away at this as you’ve been doing, I expect you’ll figure it out eventually with the help of the folks here. Best of luck.

@HHR_driver Curious if you ever figured out what the issue is? I have a the exact same issue with my 2005 Honda Civic. Replaced starter, battery, fuel pump assembly. Getting an EVAP code thrown as well but all the symptoms I read online with that code don’t say anything about having starting issues so I assumed it was not related…

I have the same problem with my golf 2003 2.0 I changed the fuel pump, fuel filter, maf, camshaft position sensor, crank sansor, spark plugs, nothing to do. I’ve been told it could be because air in the fuel line https://youtu.be/3bMrXW_M2TM